Light receiving member with non-single-crystal silicon layer containing Cr, Fe, Na, Ni and Mg

ABSTRACT

A light receiving member comprising a substrate and a light receiving layer disposed on said substrate, said light receiving layer being composed of a non-Si (H,X) material containing silicon atoms (Si) as a matrix and at least one kind of atoms selected from the group consisting of hydrogen atoms (H) and halogen atoms (X), characterized in that said light receiving layer further contains at least chromium atoms (Cr), iron atoms (Fe)f nickel atoms (Ni), sodium atoms (Na), and magnesium atoms (Mg) respectively in an amount of 0.9 atomic ppm or less. 
     The light receiving member is suitable for use as electronic devices such as electrophotographic light receiving members, solar cells, and the like, wherein it stably and continuously exhibits desirable characteristics without being deteriorated even upon repeated use over a long period of time.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an improved light receiving membercomprising a non-single crystal material containing silicon atoms as amatrix and having sensitivity to electromagnetic waves such as light(which herein means in a broad sense those lights such as ultravioletrays, visible rays, infrared rays, X-rays, and γ-rays) which is usableas electrophotographic image-forming members, image pickup devices,photoelectric conversion devices, solar cells, and the like.

2. Related Background Art

In recent years, various studies and proposals have been made ofelectronic devices such as electrophotographic image-forming members,solar cells, and thin film transistors in which non-single crystalmaterials containing silicon atoms as a matrix (hereinafter referred toas "non-Si material") including amorphous hydrogenated or/andhalogenated silicon materials (hereinafter referred to as "a-Si (H,X)material") are used.

Conventional non-Si materials such as a-Si (H,X) materials and the likeexhibit good characteristics when used in electronic devices such aselectrophotographic image-forming members, solar cells, and the like.But these non-Si materials are still problematic in terms of occurrenceof defects due to tail states or/and dangling bonds present in theirforbidden band. Particularly, for instance, in the case where danglingbonds are present in an a-Si (H,X) film to be used in such electronicdevices, such dangling bonds function as a recombination center forphoto-excited carriers or injected carriers, wherein the number ofcarriers to be practically utilized is decreased, resulting in areduction in photocurrent. Specifically, in the case of anelectrophotographic image-forming member comprising such a-Si (H,X)material, this situation entails a problem in that theelectrophotographic image-forming member does not exhibit a satisfactorysensitivity, and similarly, in the case of a solar cell comprising sucha-Si (H,X) material, this situation entails a problem in that the solarcell does not provide a satisfactory photocurrent. In addition, sincethese dangling bonds are usually present in the vicinity of the Fermilevel situated at the center of a forbidden band, in the case where thenumber of such dangling bonds is relatively large, the influence due toa hopping conduction among the dangling bonds is increased to make thea-Si (H,X) film to exhibit a reduced dark resistance. In the case of theelectrophotographic image-forming member comprising such a-Si (H,X)film, it is liable to be insufficient in terms of the chargeretentivity.

In the case of an electrophotographic image-forming member produced byusing an a-Si (H,X) film accompanied by dangling bonds and tail states,when such a member is subjected to corona charging in theelectrophotographic image-forming process, there is a tendency thatcorona ions are deposited on the electrophotographic image-formingmember, when charges from the corona ions are injected into the membersinterior through such dangling bond and tail states, there is areduction in the charge retentivity.

The tail state is closely related to light-induced fatigue for the a-Si(H,X) film. Accordingly, in order to obtain, using an a-Si (H,X) film,an electrophotographic image-forming member or a solar cell which can becontinuously used over a long period of time without being fatigued withlight irradiation, it is desired for the a-Si (H,X) film to be free oftail states. Other than this, the tail state influences the mobility ofa charge. The more the tail states, the smaller the charge mobility,wherein charges are likely to be trapped in the tail state.

In the case of an electrophotographic image-forming member produced byusing an a-Si (H,X) film accompanied by tail states, there is a tendencyof causing problems relating to residual potential, ghost appearance,dependency of the charge retentivity upon the previous exposure, anddeterioration of the photosensitivity. In addition, the quantity ofcharges to be trapped in the tail states is increased while they arebeing accumulated as the charging is repeated, to thereby cause adielectric breakdown in the electrophotographic image-forming member,resulting in defects in the reproduced images. Further in addition,those charges trapped in the tail states are liable to be releasedtherefrom during the process from image exposure to development withtoner. The charges which are released move crosswise and cause smudgingin a reproduced image.

In order to eliminate the problems relating to defect and interfacialstates which are found in the conventional a-Si (H,X) film, U.S. Pat.No. 4,217,374 or U.S. Pat. No. 4,668,599 proposes a solution byincorporating a given metal into a semiconductor comprising an a-Si(H,X) material. Other than this, U.S. Pat. No. 4,217,374 proposes atechnique of diminishing the occurrence of a localized state by using analkali metal, transition metal or rare earth metal. This publicationdescribes that the use of zinc, gold, copper, silver or manganeseprovides a sensitization effect. In addition, U.S. Pat. No. 4,668,599proposes a technique of improving the a-Si (H,X) serieselectrophotographic photosensitive device so that it does not cause asmudging for an image reproduced, by way of adding atoms of a givenmetal to the surface neighborhood region thereof to increase the contentof impurities therein or the trapped state therein thereby preventingthe occurrence of band bending.

According to these proposals, the foregoing problems in the conventionala-Si (H,X) film can be solved to a certain extent, but it is stilldifficult to eliminate the problems as desired. For instance, in anelectronic device having a light receiving layer comprising a non-Sifilm with a relatively large magnitude of defects due to tail states,dangling bonds, and the like, when the light receiving layer is dopedwith a valence electron controlling agent (specifically, an elementbelonging to group III or V of the periodic table) as the conductivitycontrolling agent, there is a problem such that the efficiency of thevalence electron controlling agent to be effectively used within thefilm is low because of those defects in the film. In order tosufficiently control valence electrons, it is required to use thevalence electron controlling agent in an increased amount. However, inthis case, a reverse problem occurs in that the presence of excessivevalence electron controlling agent causes other negative effects withinthe film, making the film further deteriorate. In addition, in the casewhere the light receiving layer has a stacked structure comprising ana-Si (H,X) film doped with an element belonging to group III or V of theperiodic table for conduction type control and a non-doped a-Si (H,X)film, there is a problem in that the foregoing defects are liable tounavoidably occur at the layer interface, resulting in a deteriorationof the characteristics of the light receiving layer.

Further, in the case where the light receiving layer has a stackedstructure comprising an a-Si (H,X) film incorporated with tin atoms (Sn)or/and germanium atoms (Ge) such as an a-SiSn (H,X) film or an a-SiGe(H,X), and a non-doped a-Si (H,X) film, defects similar to those abovedescribed are liable to occur at the layer interface to impair thecharacteristics of the light receiving layer.

SUMMARY OF THE INVENTION

The present invention makes it an object to solve the foregoing problemsin the prior art and to provide a light receiving member having a lightreceiving layer formed of a high quality non-Si semiconductoraccompanied by very few tail states or/and dangling bonds.

Another object of the present invention is to provide a light receivingmember having a light receiving layer formed of a non-Si semiconductorwhich is hardly deteriorated even upon repeated irradiation of lightover a long period of time.

A further object of the present invention is to provide a lightreceiving member having a light receiving layer formed of a non-Sisemiconductor which is hardly deteriorated even under severeenvironments of high temperature or/and high humidity.

A further object of the present invention is to provide a lightreceiving member having a light receiving layer formed of a high qualitynon-Si semiconductor, which is suitable for use as anelectrophotographic photosensitive member or a solar cell.

A further object of the present invention is to provide a lightreceiving member having a light receiving layer formed of a high qualitynon-Si semiconductor with a semiconductor junction of p-n, p-i-n, p-i ori-n in which the conductivity controlling agent contained is effected ina highly active state.

A further object of the present invention is to provide a lightreceiving member having a multi-layered light receiving layer comprisinga plurality of high quality non-Si films, which is free of the foregoingdefects in the prior art.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

The present invention has been accomplished as a result of extensivestudies by the present inventors in order to attain the above objectswhile referring to the foregoing reverse effects by the addition ofmetals.

That is, the present inventors made studies of the kinds of metalscapable of being incorporated into non-Si semiconductors such as a-Si(H,X) materials, and their amount and combination, in order to attainthe objects of the present invention. As a result, the present inventorsfound that the use of specific metals in combination and in specificamounts is markedly effective in improving the characteristics of agiven non-Si semiconductor. The present invention is based on thisfinding.

Specifically, the present inventors made extensive studies throughexperiments. As a result, it was found that even if the light receivingmember is one which comprises a substrate and a multi-layered lightreceiving layer disposed on said substrate wherein the multi-layeredlight receiving layer comprises a plurality of constituent layers eachcomprising a non-single crystal material containing silicon atoms as amatrix and at least one kind of atoms selected from the group consistingof hydrogen atoms and halogen atoms (that is, a non-Si (H,X) material),when the multi-layered light receiving layer is incorporated withchromium atoms, iron atoms, nickel atoms, sodium atoms, and magnesiumatoms respectively in a specific amount of 0.9 atomic ppm or less, theforegoing problems in the prior art are effectively solved, and theobjects of the present invention can be attained as desired. In moredetail, it was found that when, upon forming a non-Si (H,X) film by wayof plasma discharge by means of the plasma CVD technique, elemental Nabelonging to the alkali metal group, elemental Mg belonging to thealkaline earth metal group elemental Cr, elemental Fe and elemental Nieach belonging to the transition metal group are added to the plasmadischarge such that these elements are incorporated into the non-Si(H,X) deposited film respectively in a trace amount, the resultingnon-Si (H,X) film becomes one that excels in electric and opticalcharacteristics.

The reason why such a non-Si (H,X) film excelling in electric andoptical characteristics can be obtained by adding the above fiveelements upon the formation thereof is not clear at the present time,but it is prostulated that the alkali metal Na in a state of +1 in termsof oxidation number and the alkaline earth metal Mg in a state of +2 interms of oxidation number are poor in bonding power with silicon atoms.However, when these two kinds of metal atoms are ionized in the plasmawhich causes film deposition to occur on the surface of a substrate onwhich a film is being grown, these metal atoms bond with dangling bondsof the silicon atoms, wherein the dangling bonds of the silicon atomsare compensated by these Na and Mg atoms to provide the silicon atomswith increased freedom, whereby a structural relaxation is attained forthe film obtained. On the other hand, hydrogen atoms have a property ofeasily diffusing in the structure of the non-Si film, and because ofthis, they diffuse from the surface through the inside of a film beingdeposited on the substrate, wherein as the bonding energy between the Siatoms and the H atoms is greater than that between the Si atoms and theNa and Mg atoms, the Na and Mg atoms are substituted by the H atoms. Theresidual Na and Mg atoms in the film concentrate in the medium rangedefects such as microvoids to thereby decrease strains, because the Naand Mg atoms have a smaller atomic radius than the H atoms. As for thethree transition metals Cr, Fe and Ni, the Cr may take an oxidationstate of +2, +3 or +6, the Fe an oxidation state of +2 or +3, and the Nian oxidation state of +2 or +3. Any of these three kinds of metal atomsis relatively greater in terms of atomic weight, and because of this,these metal atoms are substantially not mobile when they are present inthe film. However, as above described, any of these metal atoms may takea plurality of oxidation states and, the relaxation of the Si atoms inthe structure of the non-Si film is facilitated by properly changing theoxidation state of these metal atoms.

As above described, it is considered that the Na and Mg atoms facilitatenot only the structural relaxation at the film-growing surface but alsothe structural relaxation of the medium range defects such asmicrovoids, and the Cr, Fe and Ni atoms also facilitate the structuralrelaxation at the film-growing surface. Because the Cr, Fe and Ni atomsare hardly diffused in the non-Si film, these three kinds of metal atomsare uniformly dispersed therein whereby the film is entirelystructurally relaxed.

Thus, in the case where the Na, Mg, Cr, Fe, and Ni atoms are containedtogether in the non-Si film, it is considered that desirable structuralrelaxation is attained for the microvoids in the film by virtue of theNa and Mg atoms and along with this, desirable structural relaxation isattained for the entire film structure by virtue of the Cr, Fe and Niatoms, whereby the non-Si film is entirely relaxed and as a result, thenon-Si film becomes one that excels in electric and opticalcharacteristics.

In addition, the Cr, Fe, Ni, Na, and Mg atoms which are contained in thenon-Si (H,X) film serve to compensate the recombination centers in thefilm, wherein the lifetime of a charge is prolonged and as a result, aprominent improvement is provided in the electric characteristics of thenon-Si (H,X) film.

In the present invention, the amount of the atoms of each of the abovefive metals contained in the non-Si (H,X) film is desired to be 0.9atomic ppm or less. If these five metal atoms are contained in a non-Si(H,X) film respectively in an amount exceeding 0.9 atomic ppm, numerousdefects are caused therein and as a result, the non-Si (H,X) filmbecomes poor in electric characteristics.

In the present invention, in the case of conducting the valence electroncontrol for a non-Si (H,X) film incorporated with the above five kindsof metal atoms to be formed, the proportion of a valence electroncontrolling agent to be taken into the film upon film formation isincreased because of the effects by the five kinds of metal atoms,wherein the efficiency for the valence electron controlling agent toeffectively function in the film is markedly improved. Thus, the valenceelectron control for the non-Si (H,X) film can be efficiently carriedout in a desirable state without causing defects in the film.

It is generally known that in the case of a stacked structure comprisinga valence electron-controlled non-Si (H,X) film and other non-Si (H,X)film being stacked, a charge conduction is occurred by way of theinterfacial state.

However, the stacked structure according to the present invention isfree of such problem. That is, in the case where a non-Si (H,X) filmincorporated with the foregoing five kinds of metal atoms and othernon-Si (H,X) film are stacked to obtain a stacked structure, the stackedstructure is accompanied with little interfacial state because theformer non-Si (H,X) film has few recombination centers due to theeffects of the five kinds metal atoms of facilitating the structuralrelaxation and directly compensating the recombination centers. Becauseof this, the non-Si (H,X) multi-layered structure excels in electriccharacteristics. In this stacked structure, if the non-Si (H,X) filmincorporated with the foregoing five kinds of metal atoms should alsocontain Ge atoms or/and Sn atoms, satisfactory effects are provided aswell as in the above case.

In the following, description will be made of the light receiving membercomprising the above Si (H,X) film according to the present invention,while referring to the drawings.

FIG. 1 is a schematic view illustrating a typical example of the layerconstitution of a light receiving member comprising the non-Si (H,X)film according to the present invention. In FIG. 1, reference numeral100 indicates a light receiving member comprising a substrate 101 forlight receiving member and a light receiving layer 102 having a freesurface 103 which is disposed on the substrate. The light receivinglayer 102 is constituted by a non-Si (H,X) film containing silicon atoms(Si) as a matrix, at least one kind of atoms selected from the groupconsisting of hydrogen atoms (H) and halogen atoms (X), and chromiumatoms (Cr), iron atoms (Fe), nickel atoms (Ni), sodium atoms (Na), andmagnesium atoms (Mg) respectively in an amount of 0.9 ppm or less.

Description will be made of each constituent of the light receivingmember according to the present invention.

Substrate

The substrate 101 for use in the present invention may be eitherelectroconductive or electrically insulative.

The electroconductive substrate can include, for example, metals andalloys such as NiCr, stainless steels, Al, Cr, Mo, Au, Nb, Ta, V, Ti,Pt, Pb, and the like.

The electrically insulative substrate can include, for example, filmsand sheets of synthetic resins such as polyester, polyethylene,polycarbonate, cellulose acetate, polypropylene, polyvinyl chloride,polyvinylidene chloride, polystyrene, and polyamide, and other thanthese, glass, ceramic, and paper. It is preferred that the electricallyinsulative substrate is applied with electroconductive treatment to atleast one of the surfaces thereof and disposed with a light receivinglayer on the thus treated surface.

In the case of glass, for instance, electroconductivity is applied tothe surface thereof by disposing, on the surface thereof, a thin filmmade of NiCr, Al, Cr, Mo, Au, Ir, Nb, Ta, V, Ti, Pt, Pd, InO₃, ITO (In₂O₃ +Sn), or the like. In the case of the synthetic resin film such aspolyester film, electroconductivity is applied to the surface thereof bydisposing, on the surface thereof, a thin film of a metal such as NiCr,Al, Ag, Pb, Zn, Ni, Au, Cr, Mo, Ir, Nb, Ta, V, Tl, Pt, or the like bymeans of the vacuum deposition, electron beam vapor deposition, orsputtering technique, or applying lamination with the metal to thesurface thereof.

The substrate may be of any configuration such as cylindrical, belt-likeor plate-like shape having a smooth or uneven surface.

The thickness of the substrate should be properly determined so that, inthe case where the light receiving member 100 is for use inelectrophotography, a desirable electrophotographic light receivingmember can be formed. In the event that flexibility is required for thelight receiving member, it can be made as thin as possible within arange capable of sufficiently providing the function as the substrate.However, the thickness is usually made to be greater than 10 μm in viewof ease of fabrication and handling and also in view of mechanicalstrength of the substrate 101.

In the case where the light receiving member is for use in imageformation using coherent monochromatic light such as laser beams, theelectroconductive surface of the substrate 101 may be provided withirregularities in order to prevent occurrence of defective images causedby the so-called interference fringe pattern. The formation of suchirregularities at the surface of the substrate may be conducted inaccordance with the conventional manner described, for example, inJapanese Unexamined Patent Publication No. 168156/1985, 178457/1985, or225854/1985. Other than this, in order to prevent the occurrence ofdefective images caused by the interference fringe pattern, theelectroconductive surface of the substrate 101 may be treated so as tohave an uneven surface shape provided with irregularities composed of aplurality of spherical dimples each having minute irregularities of asize which is smaller than the resolution required for the lightreceiving member 100. The formation of such spherical dimples eachhaving minute irregularities at the surface of the substrate 101 may beconducted in accordance with the conventional manner described, forexample, in Japanese Unexamined Patent Publication No. 231561/1986.

Light Receiving Layer

In the present invention, the light receiving layer comprising theforegoing non-Si (H,X) film can be properly formed by the conventionalglow discharge decomposition method such as RF glow dischargedecomposition method or microwave glow discharge decomposition method.

The raw material gas capable of supplying Si which is used for theformation of the light receiving layer can include, for example, gaseousor gasifiable silicon hydrides (silanes) such as SiH₄, Si₂ H₆, Si₃ H₈,Si₄ H10, and the like, among these, SiH₄ and Si₂ H₆ being particularlypreferred in view of ease of layer formation and good Si supplyefficiency. These Si-supplying raw material gases may be diluted withappropriate gas such as H₂ gas, He gas, Ar gas or Ne gas if necessary.

As the halogen-supplying raw material gas, there can be mentioned, forexample, gaseous or gasifiable halogen compounds such as halogen gases,halogen compounds, interhalogen compounds, and halogen-substitutedsilane derivatives. Other than these, gaseous or gasifiable siliconhalides each comprising silicon atom (Si) and halogen atom (X) as theconstituent atoms are also effective in the present invention.

Specific examples of such effectively usable halogen compounds arehalogen gases such as fluorine gas, chlorine gas, bromine gas, andiodine gas; and interhalogen compounds such as BrF, ClF, ClF₃, BrF₅,BrF₃, IF₃, IF₇, ICl, and IBr.

Specific examples of the halogen (X)-substituted silane derivative aresilicon halides such as SiF₄, Si₂ F₆, SiCl₄, SiBr₄, and the like.

The use of such a halogen atom (X)-containing silicon compound in theformation of a light receiving layer comprising the non-Si (H,X) filmaccording to the present invention by the glow discharge decompositionmethod is advantageous since a layer comprising a halogen atom(X)-containing non-Si material can be formed on a given lower layerwithout additionally using the raw material gas for supplying Si.Basically, when the halogen (X)-containing light receiving layer isformed by the glow discharge decomposition method, the layer can beformed on the substrate by using only the above-mentioned silicon halidecapable of supplying also Si. In order to facilitate the introduction ofhydrogen atoms (H) thereinto in this case, it is possible to usehydrogen gas or a hydrogen atom (H)-containing silicon compound in adesired mixing ratio together with the above compound. These rawmaterial gases are not always necessary to be separately used. It ispossible to use these raw material gases by mixing them in a desiredmixing ratio.

In the present invention, the foregoing halogen compounds and halogenatom (X)-containing silicon compounds are effectively usable as thehalogen atom-supplying raw material gas. Other than these, other gaseousor gasifiable hydrogen halides such as HF, HCl, HBr, and HI, and gaseousor gasifiable halogen-substituted silicon hydrides such as SiH₃ F, SiH₂F₂, SiHF₃, SiH₂ I₂, SiH₂ Cl₂, SiHCl₃, SiH₂ Br₂, and SiHBr₃ are alsoeffective for the formation of the light receiving layer according tothe present invention. The use of these hydrogen atom (H)-containinghalogen compounds is advantageous since the hydrogen atoms, which areextremely effective for controlling electric or photoconductiveproperties of a layer formed, are also introduced together with theintroduction of the halogen atoms (X) upon forming the light receivinglayer. In order to structurally introduce hydrogen atoms (H) into alight receiving layer formed, it is effective to cause glow discharge inthe presence of H₂ gas or silicon hydride such as SiH₄, Si₂ H₆, Si₃ H₈or Si₄ H₁₀ and the above Si-supplying raw material gas in the depositionchamber.

The amount of the hydrogen atoms (H) or/and halogen atoms (X) to becontained in a light receiving layer formed may be adjusted as desiredby controlling related conditions, i.e., the substrate temperature, theflow rate of the raw material gas capable of supplying hydrogen atom (H)or/and halogen atom (X) to be introduced into the deposition chamber,the electric discharging power, and the like.

The amount of the hydrogen atom (H) contained in the light receivinglayer is preferably in the range of 1 to 40 atomic %, more preferably inthe range of 5 to 30 atomic %, and most preferably in the range of 5 to20 atomic %.

As for the amount of the halogen atoms (X) contained in the lightreceiving layer, it is preferably in the range of 0.01 to 40 atomic %.more preferably in the range of 0.01 to 30 atomic % and, most preferablyin the range of 0.01 to 10 atomic %.

The content of the hydrogen atoms and that of the halogen atomsrespectively contained in the light receiving layer are organicallyrelated to each other. In the case where the content of the hydrogenatoms is made to be relatively large, the content of the halogen atomsis desired to be relatively small.

Incorporating Fe atoms into the light receiving layer may be properlyconducted by introducing a given gaseous raw material capable ofsupplying Fe into the deposition chamber together with other gaseousfilm-forming raw materials upon film formation. The Fe-supplying rawmaterial can include materials capable of supplying Fe which are in thegaseous state under conditions of room temperature and normal pressureor can be easily gasified at least under the layer-forming conditions.As such Fe-supplying raw material, there can be mentioned organic metalcompounds containing Fe atoms as the constituent atoms. Specificexamples are iron bromide (FeBr₄), bis(cyclopentadienyl)iron (Fe(C₅H₅)₂), and the like which are advantageous in view of ease of handlingupon the layer formation and also in view of Fe-supply efficiency. TheseFe-supplying raw materials in the gaseous state may be diluted withappropriate gas such as H₂ gas, He gas, Ar gas or Ne gas upon theirintroduction into the deposition chamber.

Incorporating Cr atoms into the light receiving layer may be properlyconducted by introducing a given gaseous raw material capable ofsupplying Cr into the deposition chamber together with other gaseousfilm-forming raw materials upon film formation. The Cr-supplying rawmaterial can include materials capable of supplying Cr which are in thegaseous state under conditions of room temperature and normal pressureor can be easily gasified at least under the layer-forming conditions.As such Cr-supplying raw material, there can be mentioned organic metalcompounds containing Cr atoms as the constituent atoms. Specificexamples are chromium bromide (CrBr₃), hexacarbonyl chromium (Cr(CO)₆),bis(cyclopentadienyl)chromium (Cr(C₅ H₅)₂), bis(benzene)chromium (Cr(C₆H₆)₂), and the like which are advantageous in view of ease of handlingupon the layer formation and also in view of Cr-supply efficiency. TheseCr-supplying raw materials in the gaseous state may be diluted withappropriate gas such as H₂ gas, He gas, Ar gas or Ne gas upon theirintroduction into the deposition chamber.

Incorporating Ni atoms into the light receiving layer may be properlyconducted by introducing a given gaseous raw material capable ofsupplying Ni into the deposition chamber together with other gaseousfilm-forming raw materials upon film formation. The Ni-supplying rawmaterial can include materials capable of supplying Ni which are in thegaseous state under conditions of room temperature and normal pressureor can be easily gasified at least under the layer-forming conditions.As such Ni-supplying raw material, there can be mentioned organic metalcompounds containing Ni atoms as the constituent atoms. Specificexamples are tetracarbonyl nickel (Ni(CO)₄), bis(cyclopentadienyl)nickel(Ni(C₅ H₅)₂), and the like which are advantageous in view of ease ofhandling upon the layer formation and also in view of Ni-supplyefficiency. These Ni-supplying raw materials in the gaseous state may bediluted with appropriate gas such as H₂ gas, He gas, Ar gas or Ne gasupon their introduction into the deposition chamber.

Incorporating Na atoms into the light receiving layer may be properlyconducted by introducing a given gaseous raw material capable ofsupplying Na into the deposition chamber together with other gaseousfilm-forming raw materials upon film formation. The Na-supplying rawmaterial can include materials capable of supplying Na which are in thegaseous state under conditions of room temperature and normal pressureor can be easily gasified at least under the layer-forming conditions.As such Na-supplying raw material, there can be mentioned organic metalcompounds containing Na atoms as the constituent atoms. Specificexamples are sodium amide (NaNH₂), and the like which are advantageousin view of ease of handling upon the layer formation and also in view ofNa-supply efficiency. These Na-supplying raw materials in the gaseousstate may be diluted with appropriate gas such as H₂ gas, He gas, Ar gasor Ne gas upon their introduction into the deposition chamber.

Incorporating Mg atoms into the light receiving layer may be properlyconducted by introducing a given gaseous raw material capable ofsupplying Mg into the deposition chamber together with other gaseousfilm-forming raw materials upon film formation. The Mg-supplying rawmaterial can include materials capable of supplying Mg which are in thegaseous state under conditions of room temperature and normal pressureor can be easily gasified at least under the layer-forming conditions.As such Mg-supplying raw material, there can be mentioned organic metalcompounds containing Mg atoms as the constituent atoms. Specificexamples are bis(cyclopentadienyl)magnesium (II), and the like which areadvantageous in view of ease of handling upon the layer formation andalso in view of Mg-supply efficiency. These Mg-supplying raw materialsin the gaseous state may be diluted with appropriate gas such as H₂ gas,He gas, Ar gas or Ne gas upon their introduction into the depositionchamber.

Other than the above, any of these metal atoms may be incorporated intothe light receiving layer by evaporating a given metal or alloy with theaction of heat in the deposition chamber upon the layer formation by theplasma CVD method.

In the present invention, the light receiving layer 102 may containconductivity controlling atoms (M). The atoms (M) may be contained inthe light receiving layer such that they are uniformly or unevenlydistributed therein in the thickness direction. The conductivitycontrolling atoms (M) may be atoms of a given element belonging to groupIII, V or VI of the periodic table. Incorporating the conductivitycontrolling atoms (M) into the light receiving layer may be properlyconducted by introducing a given gaseous raw material capable ofsupplying the group III, V or VI atoms into the deposition chambertogether with other gaseous film-forming raw materials upon filmformation. The group III atom-supplying raw material or the group Vatom-supplying raw material can include raw materials which are in thegaseous state under conditions of room temperature and normal pressureor can be easily gasified at least under the layer-forming conditions.

Specific examples of the group III atom-supplying raw material are boronhydrides such as B₂ H₆, B₄ H₁₀, B₅ H₈, B₅ H₁₁, B₆ H10, B₆ H₁₂, and B₆H₁₄, and boron halides such as BF₃, BCl₃, and BBr₃. Other than these,AlCl₃, GaCl₃, Ga(CH₃)₃, INCl₃, TlCl₃, and the like are also usable.

Specific examples of the group V atom-supplying raw material arephosphorous hydrides such as PH₃, and P₂ H₄, phosphorous halides such asPH₄ I, PF₃, PF₅, PCl₃, PCl₅, PBr₃, PBr₅, and PI₃. Other than these,AsH₃, AsF₃, AsCl₃, AsBr₃, SbH₃, SbF₃, SbF₅, SbCl₃, SbCl₃, SbCl₅, BiH₃,BiCl₃, and BiBr₃.

These raw materials capable of supplying the image quality controllingatoms (Mc) or conductivity controlling atoms (M) may be diluted withappropriate gas such as H₂ gas, He gas, Ar gas or Ne gas upon theirintroduction into the deposition chamber.

The amount of the conductivity controlling atoms contained in the lightreceiving layer is desired to be preferably in the range of 1×10⁻³ to1×10³ atomic ppm, more preferably in the range of 5×10⁻³ to 1×10² atomicppm, and most preferably in the range of 1×10⁻² to 50 atomic ppm.

The light receiving layer of the light receiving member according to thepresent invention may of such a stacked layer constitution as shown inFIG. 9. In FIG. 9, reference numeral 100 indicates anelectrophotographic light receiving member which comprises a substrate101 and a light receiving layer 102 disposed on said substrate, thelight receiving layer having a stacked structure comprising a firstlight receiving layer 102-1 and a second light receiving layer 102-2being stacked in this order from the side of the substrate 101, whereinthe latter light receiving layer has a free surface. In this embodiment,at least one of the first light receiving layer 102-1 and the secondlight receiving layer 102-2 is incorporated with the foregoing fivekinds of metal atoms. It is a matter of course that both the first lightreceiving layer 102-1 and the second light receiving layer 102-2 may beincorporated with the foregoing five kinds of metal atoms.

In a preferred embodiment, the first light receiving layer 102-1 and thesecond light receiving layer 102-2 are designed such that they aredifferent from each other in terms of function. For instance, in orderthat long wavelength light is effectively absorbed or/and in order toprevent occurrence of problems relating to interference fringe whichwill be caused in the case where incident light arrived at the substrateis reflected at the substrate, the first light receiving layer 102-1situated on the side of the substrate 101 is desired to be designed suchthat it contains germanium atoms or/and tin atoms. In this case, it isdesired for the germanium or/and tin atoms to be contained therein suchthat their concentration distribution is enhanced in a given layerregion thereof adjacent to the substrate 101. In order to prevent acharge from injecting from the substrate 101 into the light receivinglayer 102, the first light receiving layer 102-1 situated on the side ofthe substrate 101 is desired to contain the foregoing conductivitycontrolling atoms (M). In this case, the amount of the conductivitycontrolling atoms (M) contained in the first light receiving layer isdesired to be preferably in the range of 1×10⁻³ to 5×10⁴ atomic ppm,more preferably in the range of 1×10⁻² to 1×10⁴ atomic ppm, mostpreferably in the range of 1×10⁻¹ to 5×10³ atomic ppm.

The light receiving layer may further comprise a surface layer on thefree surface side for the purpose of improving the environmentresistance and wear resistance. The surface layer in this case isdesired to be composed of a non-single crystal silicon materialcontaining at least one kind of atoms selected from the group consistingof oxygen atoms, nitrogen atoms and carbon atoms, and if necessary, atleast one kind of atoms selected from the group consisting of hydrogenatoms and halogen atoms. Specific examples of such non-single crystalsilicon material are non-single crystal silicon oxide material(non-SiO), non-single crystal silicon nitride material (non-SiN),non-single crystal silicon carbide material (non-SiC), and mixtures oftwo or more of these materials.

As for the thickness of the light receiving layer, in order to make thelight receiving layer to be provided with desirable electrophotographiccharacteristics while considering economical effects therefor, it isdesired to be preferably in the range of 1 to 130 μm, more preferably inthe range of 3 to 100 μm, most preferably in the range of 5 to 60 μm.

In order to make the light receiving layer to be provided with desirablesolar cell characteristics while considering economical effectstherefor, the thickness thereof is desired to be preferably in the rangeof 0.1 to 5 μm, more preferably in the range of 0.2 to 3 μm, and mostpreferably in the range of 0.4 to 1.2 μm.

In order to form the light receiving layer comprising a specific non-Simaterial which attains the objects of the present invention, it isnecessary that the gas pressure in the deposition chamber and thesubstrate temperature upon the formation thereof be properly determinedas desired. Particularly, as for the gas pressure in the depositionchamber upon the layer formation, it should be properly determineddepending upon the kind of a light receiving layer to be formed.However, in general, it is desired to be preferably in the range of1×10⁻⁵ to 10 Torr, more preferably in the range of 1×10⁻⁴ to 3 Torr,most preferably in the range of 1×10⁻⁴ to 1 Torr.

As for the substrate temperature (Ts) upon the layer formation, itshould be properly determine kind of a upon the kind of a lightreceiving layer to be formed. For instance, in the case where the lightreceiving layer is formed of a given a-Si (H,X) material as the non-Simaterial, it is desired to be preferably in the range of 50° to 400° C.,more preferably in the range of 100° to 300° C.

In the case where the light receiving layer is formed of a given poly-Si(H,X) material as the non-Si material, the formation thereof can beconducted by any of the following methods. One method is that thesubstrate is maintained at a high temperature of 400° to 600° C., and adesired film is formed on the surface of the substrate by means of theplasma CVD technique. Another method is that a desired amorphous film isformed on the surface of the substrate maintained at a temperature ofabout 250° C. by means of the plasma CVD technique, and the amorphousfilm thus formed is subjected to annealing treatment to convert theamorphous film into a polycrystalline film. The annealing treatment inthis case can be conducted by heating the amorphous film on thesubstrate at a temperature of 400° to 600° C. for about 5 to 30 minutes,or by irradiating laser beams to the amorphous film on the substrate forabout 5 to 30 minutes.

In the case of forming the light receiving layer comprising a givennon-Si material by the glow discharge decomposition method in thepresent invention, a desired discharging electric power is supplied inthe deposition chamber depending upon the related conditions.Specifically, the discharging electric power is desired to be preferablyin the range of 5×10⁻⁵ to 10 W/cm², more preferably in the range of5×10⁻⁴ to 5 W/cm², most preferably in the range of 1×10⁻³ to 2×10⁻¹W/cm².

In the present invention, the gas pressure in the deposition chamber,the substrate temperature, the discharging electric power supplied inthe deposition chamber upon the layer formation are properly determinedrespectively in the above-described corresponding range. However, theselayer-forming parameters cannot usually be determined with easeindependent of each other. Accordingly, the parameters optimal to thelayer formation are desired to be determined based on relative andorganic relationships for forming a desired light receiving layer havingproperties as desired.

In the following, description will be made of an example of the processof producing a light receiving member according to the present inventionwith reference to the drawings.

FIGS. 2 to 4 are schematic diagrams respectively illustrating theconstitution of a fabrication apparatus suitable for the production of alight receiving member for use in electrophotography according to thepresent invention.

FIG. 2 shows the fabrication apparatus by the high frequency glowdischarge decomposition process (hereinafter referred to as RF glowdischarge decomposition process) which is suitable for the production ofa light receiving member for use in electrophotography according to thepresent invention, wherein the apparatus comprises the raw material gassupply unit 1020 and the film deposition unit 1000.

Description will be made of a typical manner of producing anelectrophotographic light receiving member using this fabricationapparatus.

In the figure, there are shown gas reservoirs 1071 and 1072. Theycontain raw material gases to form layers for the light receiving memberaccording to the present invention. The gas reservoir 1071 contains SiH₄gas (purity: 99.99%) and the gas reservoir 1072 contains H₂ gas (purity:99.9999%). Reference numeral 1051 indicates a valve for the gasreservoir 1071 and reference numeral 1052 a valve for the gas reservoir1072. Reference numerals 1031 and 1032 indicate respectively an inletvalve.

In the figure, reference numerals 1091 and 1091' indicate respectively araw material alloy composed of silicon (Si), chromium (Cr), iron (Fe),magnesium (Mg), sodium (Na), and nickel (Ni). The raw material alloy ishoused in a containment vessel 1094, and it can be moved from thecontainment vessel into a deposition chamber 1001 or from the latterinto the former through a gate valve 1007 by means of a driving means1092. In this apparatus, there is installed a heating means such as anelectric heater (not shown) for heating the raw material alloy 1091(1091').

Reference numeral 1005 indicates a cylindrical aluminum substrate.Reference numeral 1041 indicates an electric heater for heating thecylindrical substrate to a desired temperature.

In the film formation in this fabrication apparatus, prior to theentrance of the raw material gases into the deposition chamber, it isconfirmed that the valves 1051 and 1052 for the gas reservoirs 1071 and1072, a leak valve 1015 for the deposition chamber 1001, and an exhaustvalve 1093 for the containment vessel 1094 are closed and that the inletvalves 1031 and 1032, exit valves 1041 and 1042, a sub-valve 1081, andthe gate valve 1007 are opened. Then, a main valve 1016 is at firstopened to evacuate the inside of the deposition chamber 1001, the insideof the containment vessel 1094 and the insides of the gas pipe ways bymeans of a vacuum pump (not shown). Upon observing that the reading on avacuum gage 1017 became about 1×10⁻³ Tort, the sub-valve 1018, the inletvalves 1031 and 1032, and the exit valves 1041 and 1042 are closed.Thereafter, SiH₄ gas from the gas reservoir 1071 and H₂ gas from the gasreservoir 1072 are caused to flow by opening the valves 1051 and 1052,wherein the gas pressures of the raw material gases are respectivelycontrolled to 2 Kg/cm² by means of pressure controllers 1061 and 1062.Then, the inlet valves 1031 and 1032 are gradually opened to allow thetwo raw material gases to enter into mass flow controllers 1021 and1022.

Successively, the raw material alloy 1091 maintained at a desiredtemperature is moved to the position indicated by the reference numeral1091' by the driving means 1092. Then, the exit valves 1041 and 1042 andthe sub-valve 1018 are gradually opened to enter the SiH₄ gas and H₂ gasinto the deposition chamber 1001 through gas feed pipes 1008 each beingprovided with a plurality of gas liberation holes 1009. In this case,the flow rate of the SiH₄ gas and that of the H₂ gas are adjusted topredetermined respective values by means of the mass flow controllers1021 and 1022.

The inner pressure of the deposition chamber is maintained at apredetermined value by regulating the opening of the main valve 1016while observing the reading on the vacuum gage 1017. Thereafter, a RFpower source (not shown) is switched on to apply a predetermined RFpower into the deposition chamber 1001 through a matching box 1012 tocause RF glow discharge whereby producing plasma, wherein the rawmaterial alloy is sputtered by the plasma. By this, a film to be a lightreceiving layer is formed on the cylindrical aluminum substrate. Whenthe film is formed at a predetermined thickness, the RF glow dischargeis terminated, and the exit valves 1041 and 1042 and the sub-valve 1018are closed to terminate the feed of the raw material gases into thedeposition chamber 1001. Thus, the formation of the light receivinglayer is completed.

In the above, in order to incorporate the foregoing five kinds of metalatoms into the light receiving layer, instead of using the above rawmaterial alloy, it is possible to introduce appropriate raw materialgases each capable of supplying given metal atoms into the depositionchamber 1001 by using a relevant gas supply unit containing gasreservoirs for those raw material gases which is similar to the gassupply unit 1020 for the SiH₄ gas and H₂ gas.

In the above, in order to attain a desirable uniformity for the filmformed on the cylindrical aluminum substrate 1005, it is possible torotate the cylindrical substrate at a desired speed during filmformation by means of a driving means (not shown).

FIG. 4 shows the fabrication apparatus by the microwave glow dischargedecomposition process (the microwave will be hereinafter referred to asμW) which is suitable for the production of a light receiving member foruse in electrophotography according to the present invention. Thisfabrication apparatus comprises a modification of the fabricationapparatus shown in FIG. 2 in which the film deposition unit 1000 in FIG.2 is replaced by a film deposition unit 1100 by the μW glow dischargedecomposition process shown in FIG. 3, wherein the uW dischargedecomposition film deposition unit is connected to the 9as supply unit1020.

Description will be made of a typical manner of producing anelectrophotographic light receiving member using this fabricationapparatus.

In FIG. 3, reference numeral 1191 indicates an aluminum cylinder havinga raw material alloy member disposed on the surface thereof which isdedicated for the formation of a light receiving layer for theelectrophotographic light receiving member. The raw material alloymember comprises an ally member composed of silicon (Si), chromium (Cr),iron (Fe), magnesium (Mg), sodium (Na) and nickel (Ni) disposed to covera given surface area of the aluminum cylinder 1191 which iscorresponding to a 1/4 of the entire surface area of the aluminumcylinder in the longitudinal direction. The remaining 3/4 surface areaof the aluminum cylinder 1191 is covered by a silicon material. Thealuminum cylinder having the raw material alloy member thereon isinstalled such that a desired surface thereof can be faced toward aplasma generation zone 1109 upon film formation by means of a rollingmechanism (not shown).

Reference numeral 1107 indicates a cylindrical aluminium substrate onwhich a film is to be deposited which can be heated to a desiredtemperature by means of a heater (not shown). The aluminum cylinder 1191having the raw material alloy member thereon can be heated to a desiredtemperature by means of a heater (not shown).

In the film formation in this fabrication apparatus, as well as in thecase of the film formation by the abovedescribed RF glow dischargedecomposition process, prior to commencing film formation, the inside ofa deposition chamber 1101 and the insides of the gas pipe ways areevacuated so as to bring the inside of the deposition chamber 1101 to avacuum of about 5×10⁻⁶ Torr, and thereafter, the respective raw materialgases are caused to enter into the mass flow controllers 1021 and 1022.Herein, the H₂ gas reservoir used in the above case is replaced by a gasreservoir containing SiF₄ gas (purity: 99,999%).

Then, the cylinder 1191 having the raw material alloy member composed ofsilicon (Si), chromium (Cr), iron (Fe), magnesium (Mg), sodium (Na) andnickel (Ni) disposed thereon is rotated such that the raw material alloymember faces toward the plasma discharge zone 1109. Successively, theexit valves 1041 and 1042 and the sub-valve 1018 are gradually opened toenter SiH₄ gas and SiF₄ gas into the deposition chamber 1101 through aplurality of gas feed pipes 1110 each being provided with gas liberationholes (not shown). In this case, the flow rate of the SiH₄ gas and thatof the SiF₄ gas are adjusted to predetermined respective values by meansof the mass flow controllers 1021 and 1022.

The inner pressure of the deposition chamber 1101 is maintained at apredetermined value by regulating the opening of the main valve whileobserving the reading on a vacuum gage (not shown). Thereafter, a μWpower source (not shown) is switched on to apply a predeterminedmicrowave power into the plasma generation zone 1109 through a waveguide1103 and a dielectric window 1102 to cause μW glow discharge wherebyproducing plasma, wherein the raw material alloy member is sputtered bythe plasma. By this, a film to be a light receiving layer is formed oneach of the cylindrical aluminum substrates 1107. When the film isformed on each substrate at a predetermined thickness, the μW glowdischarge is terminated, and the exit valves 1041 and 1042 and thesub-valve 1018 are closed to terminate the feed of the raw materialgases into the deposition chamber 1101. Thus, the formation of the lightreceiving layer is completed.

In the above, in order to incorporate the foregoing five kinds of metalatoms into the light receiving layer, instead of using the above rawmaterial alloy member, it is possible to introduce appropriate rawmaterial gases each capable of supplying given metal atoms into thedeposition chamber 1101 by using a relevant gas supply unit containinggas reservoirs for those raw material gases which is similar to the gassupply unit 1020.

In the above, in order to attain a desirable uniformity for the filmformed on each cylindrical aluminum substrate 1107, it is possible torotate the cylindrical substrates at a desired speed during filmformation by means of a driving means (not shown).

In the following, description will be made of a typical manner ofproducing a solar cell using a continuous film-forming apparatus. FIG. 5is a schematic diagram illustrating the constitution of an example ofthe continuous film-forming apparatus suitable for the production of asolar cell. The apparatus shown in FIG. 5 is a so-called inline typefilm-forming apparatus. This inline type apparatus is suitable for theproduction of a solar cell having a stacked structure comprising aplurality of semiconductor layer being stacked. The apparatus comprisesa plurality of independent vacuum vessels including a plurality offilm-forming vacuum vessels each capable of forming a givensemiconductor film wherein the respective vacuum vessels are connectedwith each other through respective gate valves.

Particularly, the apparatus shown in FIG. 5 comprises a load lockchamber 5100 (chamber LLI) for taking a substrate into the system, apreheating chamber 5200 (chamber PH) for preheating the substrate priorto film formation, an n-type film-forming chamber 5300 (chamber N), ani-type film 1-forming chamber 5400 (chamber I₁), an i-type film2-forming chamber 5500 (chamber I₂), an i-type film 3-forming chamber5600 (chamber I₃), a p-type film-forming chamber 5700 (chamber P), acooling chamber 5800 (chamber CL) for cooling the substrate, and a loadlock chamber 5900 (LLO) for taking out the substrate, wherein thesechambers are isolated one from the other by means of a correspondinggate valve 5X50 (X=0 to 9) having an opening capable of allowing thesubstrate and a substrate holder to pass through the opening. Each ofthe chambers other than the load lock chambers is provided with a heater5X01 (X=2 to 8) such that the substrate can be heated to and maintainedat a desired temperature by the heater.

Each chamber is provided with an exhaust system comprising an exhaustpipe 5X02 (X=1 to 9) connected to a vacuuming means (not shown),comprising a rotary pump, mechanical booster pump, diffusion pump,turbo-molecular pump, cryopump, ion pump, or a combination of two ormore of these pumps. The inside of each chamber can be evacuated to adesired vacuum by operating the vacuuming means. Each exhaust system isprovided with an exhaust valve such that it is separated from the otherexhaust system. In a preferred embodiment, each exhaust system furthercomprises a throttle valve which serves to adjust the inner pressure ofthe chamber.

Each chamber is provided with a pair of gas feed pipes 5X03 (X=1 to 9)each extending from a gas reservoir (not shown) such that the adjustmentof the inner pressure of the chamber, the supply of raw material gas,gas flushing, and the like can be conducted.

In each of the chambers other than the load lock chambers, there isinstalled a discharge electrode 5X04 (X=2 to 8) for causing RF glowdischarge which is electrically connected to a RF power source (notshown) which can be properly controlled with respect to a RF poweroutputted. Each the chambers other than the load lock chambers isdesigned such that not only film formation but also sputter-etchingtreatment and plasma treatment can be conducted therein.

In each chamber, there is installed a transportation rail 5X05 (X=1 to9) provided with a transportation driving mechanism such that ittransports the substrate to the adjacent chamber in sychronism with thegate valve 5X50 (X=0 to 9).

Each film-forming chamber is provided with a metal source containmentvessel 5X06 (X=3 to 7) containing a metal source 5X08 (X=3 to 7) and ametal source containment vessel 5X07 (X=3 to 7) containing a metalsource 5X09 (X=3 to 7), wherein the metal source containment vessel 5X06is connected through a gate valve 5X10 (X=3 to 7) to the film-formingchamber and the metal source containment vessel 5X07 is connectedthrough a gate valve 5X11 (X=3 to 7) to the film-forming chamber. Eachmetal containment vessel is designed so that the metal source 5X08 orthe metal source 5X09 can be moved into the film-forming chamber. Eachof the metal source 5X08 (X=3 to 7) and the metal source 5X09 (X=3 to 7)comprises a raw material alloy which serves to form a solar cellaccording to the present invention. The raw material alloy is composedof silicon (Si), chromium (Cr), iron (Fe), magnesium (Mg), sodium (Na)and nickel (Ni). The metal source containment vessels 5X06 (X=3 to 7)and 5X07 (X=3 to 7) are desired to be designed such that each of themhas an independent gas or air supply system and a load lock structure,in order to conduct maintenance, replacement and check for the metalsources 5X08 (X=3 to 7) and 5X09 (X=3 to 7). This situation is notdescribed in the figure. Each metal source containment vessel isprovided with a heating means (not shown) for heating the metal source5X08 (X=3 to 7) or 5X09 (X=3 to 7) to a desired temperature.

In the case where the apparatus is in an idle state, for the purpose ofprevent contamination, it is desired that all the gate valves areclosed. Further, it is desired that all the heaters are alwayscontrolled to a desired temperature and that all the exhaust systems arealways maintained under operating condition. In the case where thevacuuming means comprises a rotary pump or/and a diffusion pump, ifthere is a fear that oil back may be caused, it is desired to alwaysflow argon gas or nitrogen gas (or occasionally, hydrogen gas) in thesystem.

An typical manner of producing a Shottky type solar cell according tothe present invention using the apparatus shown in FIG. 5 will bedescribed.

A well-cleaned metal substrate is introduced into the load lock chamberLLI 5100, followed by evacuating the inside thereof to a vacuum of lessthan 0.01 Torr by means of a turbo-molecular pump (not show). Argon gasis flown into the load lock chamber through the gas feed pipe 5103 tothereby subject the substrate to flushing treatment for about 20minutes. Thereafter, the flow rate of the argon gas is adjusted byclosing an exhaust valve (not shown), whereby the inner pressure of theload lock chamber is maintained at a vacuum of 0.1 Torr. In this case,the inside of the chamber PH 5200 is also maintained at a vacuum of 0.1Torr by using argon gas. When these two chambers are maintained at thesame inner pressure without conducting gas feed and gas exhaustion, thegate valve 5150 is opened and the substrate is transported from the loadlock chamber into the chamber PH 5200 by operating the transportationdriving rails 5105 and 5205. After the transportation having beenaccomplished, the gate valve 5150 is closed, when the inside of the loadlock chamber LLI 5100 is still being exhausted by the turbo-molecularpump. In the chamber PH 5200, the substrate is heated at 300° C. for 30minutes by means of the heater 5201 while introducing argon gas at aflow rate of 10 sccm through the gas feed pipe 5203, wherein the insideof the chamber is under condition of being exhausted through the exhaustpipe by operating a diffusion pump (not shown). Thereafter, a RF powerof 13.5 MHz and 150 W and a DC power of 400 V are applied through the RFdischarge electrode 5204 to conduct sputter-etching treatment for thesubstrate for 5 minutes. After this, the substrate is maintained in anargon flow atmosphere for 10 minutes, and the substrate is transportedfrom the chamber PH 5200 into the chamber N 5300, then from the chamberN 5300 into the chamber I₁ 5400, respectively in the same manner as inthe case of transporting the substrate from the chamber LLI 5100 intothe chamber PH 5200.

In the chamber I₁, the heater 5401 is so adjusted that the surfacetemperature of the substrate can be maintained at a temperature in therange of 150° to 400° C., wherein the substrate is maintained under thiscondition for 15 minutes. In this case, hydrogen gas (purity: 99.9999%)is flown thereinto through the gas feed pipe 5403 at a flow rate of 10sccm while exhausting the inside through the exhaust pipe 5402 byoperating a vacuuming means comprising a mechanical booster pump and arotary pump (not shown).

Then, a raw material gas or a gaseous mixture containing said rawmaterial gas is introduced into the film-forming chamber through the gasfeed pie 5403. The gate valve 5410 is opened to enter a metal source A5408 housed in the metal source A containment vessel (the MA vessel)5406 into the chamber I₁, and the metal source is positioned in closeproximity to the substrate. The inner pressure is adjusted to a vacuumin the range of 0.01 to 10 Torr. Then, a RF power of 0.5 to 400 W isapplied through the RF discharge electrode 5405 to cause RF dischargewhereby producing plasma, wherein the metal source is sputtered by theplasma. This discharging is continued for 3 to 70 minutes, to therebyform an a-Si layer of about 0.04 to 4 micron meters in thickness on thesubstrate. After the film formation, the discharging is terminated, themetal source A 5408 is returned into the MA vessel, and the substrate ismaintained in a hydrogen gas flow atmosphere for 10 minutes.

Thereafter, the substrate is transported into the chamber CL 5800 in thesame transportation manner as in the above case. In the chamber CL 5800,the heater 5801 is under condition of OFF, and the substrate temperaturecan be monitored. Hydrogen gas is flown thereinto to cool the substrateto a temperature of less than 50° C. while exhausting the inside byoperating the exhaust system (not shown). When the substrate is cooledto a temperature of less than 50° C., the substrate is transported intothe load lock chamber LLO 5900 in the same transportation manner as inthe above case. The exhaust valve (not shown) of the exhaust pipe 5902is closed, and argon gas is introduced into the load lock chamberthrough the gas feed pipe 5903 to thereby make the inner pressure to beatmospheric pressure, wherein the gate valve 5950 is opened and thesubstrate is taken out from the system. After this, the gate valve isclosed, the inside of the chamber LLO 5900 is again subjected to argongas flushing treatment by opening the exhaust valve. Thus, a desirablea-Si film according to the present invention is formed on the metalsubstrate. After the film formation having been completed, thefilm-forming apparatus of FIG. 5 is returned into an idle state.

The substrate having the a-Si film formed thereon is introduced into aconventional resistance heating evaporation apparatus provided with aheat source comprising a tungsten wire, wherein a 70 Å thick Au film asa light incident side semitransparent electrode is deposited on the a-Sifilm. Thus, there is obtained a Shottky type solar cell.

In the above, in order to incorporate the foregoing five kinds of metalatoms into the a-Si film, instead of using the above raw material alloymember, it is possible to use appropriate raw material gases eachcapable of supplying given metal atoms. The introduction of those rawmaterial gases may be properly conducted by using an appropriate rawmaterial supply system similar to the gas supply system comprising thefeed pipes 5X03 (X=1 to 9).

In the following, description will be made of apparatus suitable forproduction of an electrophotographic light receiving member or a solarcell each having the foregoing light receiving layer containing aconductivity controlling element and a manner of producing these deviceswith reference to FIGS. 6 to 8 and FIG. 5.

FIG. 6 shows the fabrication apparatus by the high frequency glowdischarge decomposition process (hereinafter referred to as RF glowdischarge decomposition process) which is suitable for the production ofa light receiving member for use in electrophotography according to thepresent invention, wherein the apparatus comprises the raw material gassupply unit 1020 and the film deposition unit 1000.

Description will be made of a typical manner of producing anelectrophotographic light receiving member using this fabricationapparatus.

In FIG. 6, there are shown gas reservoirs 1071 through 1074. Theycontain raw material gases to form layers for the light receiving memberaccording to the present invention. The gas reservoir 1071 contains SiH₄gas (purity: 99.99%), the gas reservoir 1072 contains H₂ gas (purity:99.9999%), the gas reservoir 1073 contains B₂ H₆ gas diluted with H₂ gas(purity: 99.999%) (this will be hereinafter referred to as "B₂ H₆ /H₂gas"), and the gas reservoir 1074 contains PH₃ gas diluted with H₂ gas(purity: 99.999%) (this will be hereinafter referred to as "PH₃ /H₂gas"). Reference numeral 1051 indicates a valve for the gas reservoir1071, reference numeral 1052 a valve for the gas reservoir 1072,reference numeral 1053 a valve for the gas reservoir 1073, and referencenumeral 1054 a valve for the gas reservoir 1074. When these gasreservoirs are attached to the gas supply unit 1020, the pipe waysbetween the valves 1051 to 1054 and inlet valves 1031 to 1034 arerespectively charged with the corresponding gas.

In FIG. 6, reference numerals 1091 and 1091' indicate respectively a rawmaterial alloy composed of silicon (Si), chromium (Cr), iron (Fe),magnesium (Mg), sodium (Na), and nickel (Ni). The raw material alloy ishoused in a containment vessel 1094, and it can be moved from thecontainment vessel into a deposition chamber 1001 or from the latterinto the former through a gate valve 1007 by means of a driving means1092. In this apparatus, there is installed a heating means such as anelectric heater (not shown) for heating the raw material alloy as wellas in the case of the apparatus shown in FIG. 2.

Reference numeral 1005 indicates a cylindrical aluminum substrate.Reference numeral 1041 indicates an electric heater for heating thecylindrical substrate to a desired temperature.

In the film formation in this fabrication apparatus, prior to theentrance of the raw material gases into the deposition chamber, it isconfirmed that the valves 1051 through 1054 for the gas reservoirs 1071through 1074, a leak valve 1015 for the deposition chamber 1001, and anexhaust valve 1093 for the containment vessel 1094 are closed and thatthe inlet valves 1031 through 1034, exit valves 1041 through 1044, asub-valve 1081, and the gate valve 1007 are opened. Then, a main valve1016 is at first opened to evacuate the inside of the deposition chamber1001, the inside of the containment vessel 1094 and the insides of thegas pipe ways by means of a vacuum pump (not shown). Upon observing thatthe reading on a vacuum gage 1017 became about 1×10⁻³ Torr, thesub-valve 1018, the inlet valves 1031 through 1034, and the exit valves1041 through 1044 are closed. Thereafter, SiH₄ gas from the gasreservoir 1071, H₂ gas from the gas reservoir 1072, B₂ H₆ /H₂ gas fromthe gas reservoir 1073, and PH₃ /H₂ gas from the reservoir 1074 arecaused to flow by opening the valves 1051 through 1054, wherein the gaspressures of the raw material gases are respectively controlled to 2Kg/cm² by means of pressure controllers 1061 through 1064. Then, theinlet valves 1031 through 1034 are gradually opened to allow the aboveraw material gases to enter into mass flow controllers 1021 through1024.

Successively, the raw material alloy 1091 maintained at a desiredtemperature is moved to the position indicated by the reference numeral1091' by the driving means 1092. Then, the exit valves 1041 through 1043and the sub-valve 1018 are gradually opened to enter the SiH₄ gas, H₂gas and B₂ H₆ /H₂ gas into the deposition chamber 1001 through gas feedpipes 1008 each being provided with a plurality of gas liberation holes1009. In this case, the flow rate of the SiH₄ gas, that of the H₂ gas,and that of the B₂ H₆ /H₂ gas are adjusted to predetermined respectivevalues by means of the mass flow controllers 1021 through 1023.

The inner pressure of the deposition chamber 1001 is maintained at apredetermined value by regulating the opening of the main valve 1016while observing the reading on the vacuum gage 1017. Thereafter, a RFpower source (not shown) is switched on to apply a predetermined RFpower into the deposition chamber 1001 through a matching box 1012 tocause RF glow discharge whereby producing plasma, wherein the rawmaterial alloy is sputtered by the plasma. By this, a film to be a lightreceiving layer for electrophotographic light receiving member is formedon the cylindrical aluminum substrate 1005. When the film is formed at apredetermined thickness, the RF glow discharge is terminated, and theexit valves 1041 through 1043 and the sub-valve are closed to terminatethe feed of the raw material gases into the deposition chamber 1001.Thus, the formation of the light receiving layer is completed.

In the above, in order to incorporate the foregoing five kinds of metalatoms into the light receiving layer, instead of using the above rawmaterial alloy, it is possible to introduce appropriate raw materialgases each capable of supplying given metal atoms into the depositionchamber 1001 by using a relevant gas supply unit containing gasreservoirs for those raw material gases.

If necessary, it is possible to form a second light receiving layer onthe light receiving layer formed in the above, wherein the previouslyformed layer is made to be a first light receiving layer. In this case,the formation of the second light receiving layer may be conducted inthe following manner.

That is, in the case where the raw material alloy 1091' is not used forthe formation of the second layer, the raw material alloy 1091' isreturned to the original position 1091 by means of the driving means1092, and the gate valve 1007 is closed. Then, the sub-valve 1018 isonce closed. Thereafter, the exit valves 1041 and 1042 and the sub-valve1018 are gradually opened to enter SiH₄ gas and H₂ gas into thedeposition chamber 1001 through the gas liberation holes 1009 of the gasfeed pipes 1008. In this case, the flow rate of the SiH₄ gas and that ofthe H₂ gas are adjusted to predetermined respective values by means ofthe mass flow controllers 1021 and 1022.

The inner pressure of the deposition chamber 1001 is maintained at apredetermined value by regulating the opening of the main valve 1016while observing the reading on the vacuum gage 1017. Thereafter, the RFpower source (not shown) is switched on to apply a predetermined RFpower into the deposition chamber 1001 through the matching box 1012 tocause RF glow discharge whereby producing plasma. By this, a film to bethe second light receiving layer is formed on the previously formedfirst light receiving layer. When the film is formed at a predeterminedthickness, the RF glow discharge is terminated, and the exit valves 1041and 1042 and the sub-valve 1018 are closed to terminate the feed of theraw material gases into the deposition chamber 1001. Thus, the formationof the second light receiving layer is completed.

Further if necessary, it is possible to form a third light receivinglayer on the second light receiving layer. In this case, the formationof the third light receiving layer may be conducted in the followingmanner.

That is, in the case where the raw material alloy has not been used forthe formation of the second layer, the inside of the containment vessel1094 is evacuated by opening the exhaust valve 1093, and thereafter theexhaust valve 1093 is closed. Then, the gate valve 1007 is opened andthe raw material alloy 1091 is moved to the position 1091' by means ofthe driving means 1092. Thereafter, the exit valves 1041, 1042 and 1044and the sub-valve 1018 are gradually opened to enter SiH₄ gas, H₂ gasand PH₃ /H₂ gas into the deposition chamber 1001 through the gasliberation holes 1009 of the gas feed pipes 1008. In this case, the flowrate of the SiH₄ gas, that of the H₂ gas and that of the PH₃ /H₂ gas areadjusted to predetermined respective values by means of the mass flowcontrollers 1021, 1022 and 1024.

The inner pressure of the deposition chamber 1001 is maintained at apredetermined value by regulating the opening of the main valve 1016while observing the reading on the vacuum gage 1017. Thereafter, the RFpower source (not shown) is switched on to apply a predetermined RFpower into the deposition chamber 1001 through the matching box 1012 tocause RF glow discharge whereby producing plasma, wherein the rawmaterial alloy is sputtered by the plasma. By this, a film to be thethird light receiving layer is formed on the previously formed secondlight receiving layer. When the film is formed at a predeterminedthickness, the RF glow discharge is terminated, and the exit valves1041, 1042 and 1044 and the sub-valve 1018 are closed to terminate thefeed of the raw material gases into the deposition chamber 1001. Thus,the formation of the third light receiving layer is completed.

Of the exit valves 1041 to 1044, all of the exit valves other than thoserequired for upon forming the respective layers are of course closed.Further, upon forming the respective layers, the inside of the system isonce evacuated to a high vacuum degree as required by closing the exitvalves 1041 through 1044 while opening the sub-valve 1018, the gatevalve 1007 and the exhaust valve 1093 and fully opening main valve 1016for avoiding that the gases having been used for forming the previousfilm are left in the deposition chamber 1001, in the pipe ways from theexit valves 1041 trough 1044 to the inside of the deposition chamber1001, and in the containment vessel 1094.

In the case of using the raw material alloy 1091 for forming therespective layers, the procedures of evacuating the inside of thecontainment vessel 1094 by opening the exhaust valve 1093, closing theexhaust valve 1093, opening the gate valve 1007, and moving the rawmaterial alloy 1091 to the position 1091' by means of the driving means1092 are conducted. In the case of not using the raw material alloy1091, the procedures of returning the raw material alloy 1091' to theoriginal position 1091 and closing the gate valve 1007 are conducted. Aspreviously described, instead of the raw material alloy, it is possibleto use appropriate raw material gases capable of supplying the foregoingmetal atoms upon forming a given light receiving layer.

Further, during the film-forming operation, it is possible to rotate thecylindrical aluminum substrate 1005 at a desired rotational speed bymeans of a rotating means (not shown) in order to attain a desirableuniformity for a film obtained.

FIG. 8 shows the fabrication apparatus by the microwave glow dischargedecomposition process (the microwave will be hereinafter referred to asμW) which is suitable for the production of a light receiving member foruse in electrophotography according to the present invention. Thisfabrication apparatus comprises a modification of the fabricationapparatus shown in FIG. 6 in which the film deposition unit 1000 in FIG.6 is replaced by a film deposition unit 1100 by the μW glow dischargedecomposition process shown in FIG. 7, wherein the μW dischargedecomposition film deposition unit is connected to the gas supply unit1020.

Description will be made of a typical manner of producing anelectrophotographic light receiving member using this fabricationapparatus.

In the figures, reference numeral 1191 indicates an aluminum cylinderhaving a raw material alloy member disposed on the surface thereof whichis dedicated for the formation of a light receiving layer for theelectrophotographic light receiving member as well as in the case ofFIG. 3. The raw material alloy member comprises an ally member composedof silicon (Si), chromium (Cr), iron (Fe), magnesium (Mg), sodium (Na)and nickel (Ni) disposed to cover a given surface area of the aluminumcylinder which is corresponding to a 1/4 of the entire surface area ofthe aluminum cylinder in the longitudinal direction. The remaining 3/4surface area of the aluminum cylinder is covered by a silicon material.The aluminum cylinder having the raw material alloy member thereon isinstalled such that a desired surface thereof can be faced toward aplasma generation zone 1109 upon film formation by means of a rollingmechanism (not shown).

Reference numeral 1107 indicates a cylindrical aluminium substrate onwhich a film is to be deposited which can be heated to a desiredtemperature by means of a heater (not shown). The aluminum cylinder 1191having the raw material alloy member thereon can be heated to a desiredtemperature by means of a heater (not shown).

In the film formation in this fabrication apparatus, as well as in thecase of the film formation by the above-described RF glow dischargedecomposition process, prior to commencing film formation, the inside ofthe deposition chamber 1101 and the insides of the gas pipe ways areevacuated so as to bring the inside of the deposition chamber 1101 to avacuum of about 5×10⁻⁶ Torr, and thereafter, the respective raw materialgases are caused to enter into the mass flow controllers 1021 to 1025.Herein, the H₂ gas reservoir used in the above case is replaced by a gasreservoir containing SiF₄ gas purity: 99.999%).

Then, the cylinder 1191 having the raw material alloy member composed ofsilicon (Si), chromium (Cr), iron (Fe), magnesium (Mg), sodium (Na) andnickel (Ni) disposed thereon is rotated such that the raw material alloymember faces toward the plasma discharge zone 1109. Successively, theexit valves 1041 through 1043 and the sub-valve 1018 are graduallyopened to enter SiH₄ gas, SiF₄ gas and B₂ H₆ /H₂ gas into the depositionchamber 1101 through the gas liberation holes (not shown) of the gasfeed pipes 1110. In this case, the flow rate of the SiH₄ gas, that ofthe SiF₄ gas and that of the B₂ H₆ /H₂ gas are adjusted to predeterminedrespective values by means of the mass flow controllers 1021 through1023.

The inner pressure of the deposition chamber 1101 is maintained at apredetermined value by regulating the opening of the main valve whileobserving the reading on the vacuum gage (not shown). Thereafter, the μWpower source (not shown) is switched on to apply a predeterminedmicrowave power into the plasma generation zone 1109 through thewaveguide 1103 and the dielectric window 1102 to cause μW glow dischargewhereby producing plasma, wherein the raw material alloy member issputtered by the plasma. By this, a film to be a light receiving layerfor electrophotographic light receiving member is formed on each of thecylindrical aluminum substrates 1107. When the film is formed on eachsubstrate at a predetermined thickness, the μW glow discharge isterminated, and the exit valves 1041 through 1043 and the sub-valve areclosed to terminate the feed of the raw material gases into thedeposition chamber 1101. Thus, the formation of the light receivinglayer is completed.

If necessary, it is possible to form a second light receiving layer onthe light receiving layer formed in the above, wherein the previouslyformed layer is made to be a first light receiving layer. In this case,the formation of the second light receiving layer may be conducted inthe following manner.

That is, in the case where the raw material alloy member is not used forthe formation of the second light receiving layer, the cylinder 1191 isrotated such that the surface thereof having the silicon materialthereon faces toward the plasma discharge zone 1109. Successively, thesub-valve 1018 is once closed. Then, the exit valves 1041 and 1042 andthe sub-valve 1018 are gradually opened to enter SiH₄ gas and SiF₄ gasinto the deposition chamber 1101 through the gas liberation holes (notshown) of the gas feed pipes 1110. In this case, the flow rate of theSiH₄ gas and that of the SiF₄ gas are adjusted to predeterminedrespective values by means of the mass flow controllers 1021 and 1022.

The inner pressure of the deposition chamber 1101 is maintained at apredetermined value by regulating the opening of the main valve whileobserving the reading on the vacuum gage (not shown). Thereafter, the μWpower source (not shown) is switched on to apply a predeterminedmicrowave power into the plasma generation zone 1109 through thewaveguide 1103 and the dielectric window 1102 to cause uW glow dischargewhereby producing plasma. By this, a film to be the second lightreceiving layer is formed on the first light receiving layer previouslyformed each of the cylindrical aluminum substrates. When the film isformed on each substrate at a predetermined thickness, the μW glowdischarge is terminated, and the exit valves 1041 and 1042 and thesub-valve 1018 are closed to terminate the feed of the raw materialgases into the deposition chamber 1101. Thus, the formation of thesecond light receiving layer is completed.

Further if necessary, it is possible to form a third light receivinglayer on the second light receiving layer. In this case, the formationof the third light receiving layer may be conducted in the followingmanner.

That is, the cylinder 1191 is rotated such that the surface thereofhaving the raw material alloy member composed of silicon (Si), chromium(Cr), iron (Fe), magnesium (Mg), sodium (Na) and nickel (Ni) thereonfaces toward the plasma discharge zone 1109. Successively, the exitvalves 1041, 1042 and 1044 and the sub-valve 1018 are gradually openedto enter SiH₄ gas, SiF₄ gas and PH₃ /H₂ gas into the deposition chamber1101 through the gas liberation holes (not shown) of the gas feed pipes1110. In this case, the flow rate of the SiH₄ gas, that of the SiF₄ gasand that of the PH₃ /H₂ gas are adjusted to predetermined respectivevalues by means of the mass flow controllers 1021, 1022 and 1024.

The inner pressure of the deposition chamber 1101 is maintained at apredetermined value by regulating the opening of the main valve whileobserving the reading on the vacuum gage (not shown). Thereafter, the μWpower source (not shown) is switched on to apply a predeterminedmicrowave power into the plasma generation zone 1109 through thewaveguide 1103 and the dielectric window 1102 to cause μW glow dischargewhereby producing plasma, wherein the raw material alloy member issputtered by the plasma. By this, a film to be the third light receivinglayer is formed on the second light receiving layer previously formed oneach of the cylindrical aluminum substrates. When the film is formed oneach substrate at a predetermined thickness, the μW glow discharge isterminated, and the exit valves 1041, 1042 and 1044 and the sub-valveare closed to terminate the feed of the raw material gases into thedeposition chamber 1101. Thus, the formation of the third lightreceiving layer is completed.

Of the exit valves 1041 to 1044, all of the exit valves other than thoserequired for upon forming the respective layers are of course closed.Further, upon forming the respective layers, the inside of the system isonce evacuated to a high vacuum degree as required by closing the exitvalves 1041 through 1044 while opening the sub-valve 1018 and fullyopening main valve 1016 for avoiding that the gases having been used forforming the previous film are left in the deposition chamber 1001 and inthe pipe ways from the exit valves 1041 trough 1044 to the inside of thedeposition chamber 1001.

As apparent from the above description, upon forming the respectivelayers, the procedure of facing the face comprised of the siliconmaterial of the foregoing cylinder toward the plasma generation zone1109 by means of the rolling mechanism (not shown) or the procedure offacing the face comprised of the raw material alloy member composed ofsilicon (Si), chromium (Cr), iron (Fe), magnesium (Mg), sodium (Na) andnickel (Ni) toward the plasma discharge zone 1109 by means of therolling mechanism is conducted when required.

Further, during the film-forming operation, it is possible to rotateeach of the cylindrical aluminum substrates 1107 at a desired rotationalspeed by means the rotating means (not shown) in order to attain adesirable uniformity for a film formed on each cylindrical aluminumsubstrate. Further in addition, instead of the raw material alloymember, it is possible to use appropriate raw material gases capable ofsupplying the foregoing metal atoms upon forming a given light receivinglayer.

In the following, description will be made of a typical manner ofproducing other solar cell using the apparatus shown in FIG. 5. Thefundamental film-forming manner using the apparatus shown in FIG. 5 isas has described in the above.

In the following, a typical manner of producing a pin junction typesolar cell using the apparatus shown in FIG. 5 will be described.

In this case, the procedures until the chamber N are the same as thosein the foregoing case of producing the Shottky type solar cell. In thechamber N, the heater 5301 is so adjusted that the surface temperatureof the substrate can be maintained at a temperature in the range of 150°to 400° C., wherein the substrate is maintained under this condition. Inthis case, argon gas (purity: 99.9999%) is flown into the chamberthrough the gas feed pipe 5303 at a flow rate of 20 sccm whileexhausting the inside through the exhaust pipe 5302 by operating thevacuuming means comprising a mechanical booster pump and a rotary pump(not shown).

Then, an n-type dopant-containing raw material gas or a gaseous mixturecontaining said raw material gas is introduced into the chamber Nthrough the gas feed pipe 5303. The inner pressure of the chamber N ismaintained at a value of 0.01 to 10 Torr. A RF power of 0.5 to 400 W isapplied through the RF discharge electrode 5304 to cause RF dischargewhereby producing plasma. This discharging is continued for 0.1 to 10minutes, to thereby form an about 0.005 to 0.2 micron meters thick a-Silayer having an n-type conductivity. After the layer formation, thedischarging is terminated, and the substrate is maintained in an argongas flow atmosphere for 10 minutes. Thereafter, the substrate istransported from the chamber N 5300 into the chamber I₁ 5400 in the samemanner as in the foregoing case of transporting the substrate from thechamber LLI 5100 into the chamber PH 5200.

In the chamber I₁ 5400, the heater 5401 is so adjusted that the surfacetemperature of the substrate can be maintained at a temperature in therange of 150° to 400° C., wherein the substrate is maintained under thiscondition for 15 minutes. In this case, hydrogen gas (purity: 99.9999%)is flown thereinto through the gas feed pipe 5403 at a flow rate of 10sccm while exhausting the inside through the exhaust pipe 5402 byoperating the vacuuming means comprising the mechanical booster pump andthe rotary pump (not shown).

Then, a raw material gas or a gaseous mixture containing said rawmaterial gas is introduced into the chamber I₁ through the gas feed pie5403. The gate valve 5410 is opened to enter the metal source A 5408housed in the metal source A containment vessel (the MA vessel) 5406into the chamber I₁, and the metal source is positioned in closeproximity to the substrate. The inner pressure is adjusted to a vacuumin the range of 0.01 to 10 Torr. Then, a RF power of 0.5 to 400 W isapplied through the RF discharge electrode 5405 to cause RF dischargewhereby producing plasma, wherein the metal source is sputtered by theplasma. This discharging is continued for 3 to 70 minutes, to therebyform an a-Si layer of about 0.04 to 4 micron meters in thickness on thesubstrate. After the layer formation, the discharging is terminated, themetal source A 5408 is returned into the MA vessel, and the substrate ismaintained in a hydrogen gas flow atmosphere for 10 minutes. Thesubstrate is transported from the chamber I₁ 5400 into the chamber I₂5500, then from the chamber I₂ 5500 into the chamber I₃ 5600, furtherfrom the chamber I₃ 5600 into the chamber P, respectively in the samemanner as in the foregoing case of transporting the substrate from thechamber LLI 5100 into the chamber PH 5200. In the chamber P, the heater5701 is so adjusted that the surface temperature of the substrate can bemaintained at a temperature in the range of 150° to 400° C., wherein thesubstrate is maintained under this condition. In this case, argon gas(purity: 99.9999%) is flown into the chamber through the gas feed pipe5703 at a flow rate of 20 sccm while exhausting the inside through theexhaust pipe 5702 by operating the vacuuming means comprising amechanical booster pump and a rotary pump (not shown).

Then, a p-type dopant-containing raw material gas or a gaseous mixturecontaining said raw material gas is introduced into the chamber Pthrough the gas feed pipe 5703. The inner pressure of the chamber P ismaintained at a value of 0.01 to 10 Torr. A RF power of 0.5 to 400 W isapplied through the RF discharge electrode 5704 to cause RF dischargewhereby producing plasma. This discharging is continued for 0.1 to 10minutes, to thereby form an about 0.005 to 0.2 micron meters thick a-Silayer having a p-type conductivity. After the layer formation, thedischarging is terminated, and the substrate is maintained in an argongas flow atmosphere for 10 minutes.

Thereafter, following the procedures employed in the foregoing case ofproducing the Shottky type solar cell, the substrate is transported intothe chamber CL 5800, and it is taken out from the chamber LLO. On thepin structure formed on the substrate, an upper electrode is formed by aconventional method, to thereby obtain a solar cell. For instance, theupper electrode may be formed by forming a 150 Å thick ITO film by meansof the sputtering technique, followed by forming an Ag grid electrode.

In the following, description will be made of a typical manner ofproducing an electrophotographic light receiving member of theconstitution shown in FIG. 9 in which the first light receiving layer102-1 is incorporated with a conductivity controlling material (M) (avalence electron controlling agent) so that it has a function ofpreventing a charge from injecting from the substrate 101.

The second light receiving layer 102-2 in this case is the same as thatin the foregoing case. Therefore, description about this is omittedherein.

In the present invention, the valence controlling agent-containing firstlight receiving layer can be properly formed by the conventional glowdischarge decomposition method such as RF glow discharge decompositionmethod or microwave glow discharge decomposition method, as well as inthe foregoing case.

The raw material gas capable of supplying Si which is used for theformation of said first light receiving layer can include, for example,gaseous or gasifiable silicon hydrides (silanes) such as SiH₄, Si₂ H₆,Si₃ H₈, Si₄ H₁₀, and the like, among these, SiH₄ and Si₂ H₆ beingparticularly preferred in view of ease of layer formation and good Sisupply efficiency. These Si-supplying raw material gases may be dilutedwith appropriate gas such as H₂ gas, He gas, Ar gas or Ne gas ifnecessary.

As the halogen-supplying raw material gas, there can be mentioned, forexample, gaseous or gasifiable halogen compounds such as halogen gases,halogen compounds, interhalogen compounds, and halogen-substitutedsilane derivatives. Other than these, gaseous or gasifiable siliconhalides each comprising silicon atom (Si) and halogen atom (X) as theconstituent atoms, and gaseous or gasifiable hydrogenated siliconcompounds each containing halogen atom (X) as the constituent atom arealso effective in the present invention.

Detailed explanation about the above halogen compounds and halogen(X)-containing silicon compounds (that is, the halogen (X)-substitutedsilane derivatives) is omitted herein, because these compounds have beenpreviously exampled.

The use of such halogen atom (X)-containing silicon compound in theformation of the first light receiving layer comprising a halogen atom(X)-containing non-Si material of the electrophotographic lightreceiving member according to the present invention by the glowdischarge decomposition method is advantageous since the layer can beformed without using an additional hydrogenated silicon gas as the rawmaterial for supplying Si.

Basically, when the halogen atom (X)-containing first light receivinglayer by the glow discharge decomposition method, the layer can beformed on a desired substrate using only the above-described siliconhalide capable of supplying also Si. In order to facilitate theintroduction of hydrogen atoms (H) into the layer, it is possible to usehydrogen gas or a hydrogen atom (H)-containing silicon compound gas in adesired mixing ratio together with said raw material. These raw materialgases are not necessary to be separately used. It is possible to usethese raw material gases by mixing them in a desired mixing ratio.

In the present invention, the foregoing halogen compounds and halogenatom (X)-containing silicon compounds are effectively usable as thehalogen atom-supplying raw material gas. Other than these, those gaseousor gasifiable halogen-substituted silicon hydrides which have beenpreviously exampled are also effective for the formation of the abovefirst light receiving layer. The use of such hydrogen atom(H)-containing halogen compound is advantageous since hydrogen atoms,which are extremely effective in view of the control for the electric orphotoconductive properties of a layer formed, are also introducedtogether with the introduction of the halogen atoms (X) upon forming theabove first light receiving layer.

In order to structurally introduce hydrogen atoms (H) into the firstlight receiving layer, it is effective to cause glow discharge in thepresence of H₂ gas or silicon hydride such as SiH₄, Si₂ H₆, Si₃ H₈, orSi₄ H₁₀ in the deposition chamber.

The amount of the hydrogen atoms (H) or/and halogen atoms (X) to becontained may be adjusted as desired by properly controlling relatedconditions, i.e., the substrate temperature, the flow rate of the rawmaterial gas capable of supplying hydrogen atom (H) or/and halogen atom(X) to be introduced into the deposition chamber, the electricdischarging power, and the like.

The amount of the hydrogen atoms (H) contained in the above first lightreceiving layer is preferably in the range of 1 to 40 atomic %, morepreferably in the range of 5 to 30 atomic %, most preferably in therange of 5 to 20 atomic %. As for the amount of the halogen atoms (X)contained in the above first light receiving layer, it is preferably inthe range of 0.01 to 40 atomic %, more preferably in the range of 0.01to 30 atomic %, most preferably in the range of 0.01 to 10 atomic %.

The content of the hydrogen atoms and that of the halogen atoms areorganically related with each other. In the case where the content ofthe hydrogen atoms is made to be relatively great, the content of thehalogen atoms is desired to be as small as possible.

In the present invention, to structurally incorporate atoms (M) of agiven group III or V element of the periodic table into the above firstlight receiving layer may be properly conducted by introducing a givengaseous raw material capable of supplying the atoms (M) into thedeposition chamber together with other film-forming raw material gasupon the formation of the first light receiving layer. The group IIIatom-supplying raw material or the group V atom-supplying raw materialcan include raw materials which are in the gaseous state underconditions of room temperature and normal pressure or can be easilygasified at least under the layer-forming conditions.

Specifically, the group III atom-supplying raw material can includethose which have been previously described. The group V atom-supplyingraw material can include those which have been previously described.These raw materials capable of supplying the conductivity controllingatoms (M) may diluted with appropriate gas such as H₂ gas, He gas, Argas or Ne gas upon their introduction into the deposition chamber.

The layer constitution of the light receiving member according to thepresent invention is not limited to those above described only, but itcan be modified into any other appropriate layer constitution as long asthe objects of the present invention can be attained.

The present invention will be described in more detail with reference tothe following experiments, which are however not intended to restrictthe scope of the present invention to these experiments.

Experiment 1 and Comparative Experiments 1 to 5

Experiment 1

In accordance with the foregoing film-forming manner using the apparatusshown in FIG. 2 and under the conditions shown in Table 1, there wereprepared a plurality of electrophotographic light receiving members,wherein as the substrate, there was used a cylindrical aluminumsubstrate of 108 mm in outer diameter and having a mirror ground surfacein every case.

In addition, the above film-forming procedures under the conditionsshown in Table 1 were repeated, except that the layer thickness waschanged to 5 μm and a quartz plate was used as the substrate, to therebyobtain a test sample having the same layer as in the above.

Comparative Experiment 1

The procedures of Experiment 1 were repeated, except that a raw materialalloy composed of 99.80 atomic % of silicon (Si) and 0.20 atomic % ofchromium (Cr) was used as the raw material alloy 1091, to there byobtain a plurality of electrophotographic light receiving members and atest sample.

Comparative Experiment 2

The procedures of Experiment 1 were repeated, except that a raw materialalloy composed of 99.80 atomic % of silicon (Si) and 0.20 atomic % ofiron (Fe) was used as the raw material alloy 1091, to there by obtain aplurality of electrophotographic light receiving members and a testsample.

Comparative Experiment 3

The procedures of Experiment 1 were repeated, except that a raw materialalloy composed of 99.65 atomic % of silicon (Si) and 0.35 atomic % ofmagnesium (Mg) was used as the raw material alloy 1091, to there byobtain a plurality of electrophotographic light receiving members and atest sample.

Comparative Experiment 4

The procedures of Experiment 1 were repeated, except that a raw materialalloy composed of 99.65 atomic % of silicon (Si) and 0.35 atomic % ofsodium (Na) was used as the raw material alloy 1091, to there by obtaina plurality of electrophotographic light receiving members and a testsample.

Comparative Experiment 5

The procedures of Experiment 1 were repeated, except that a raw materialalloy composed of 99.80 atomic % of silicon (Si) and 0.20 atomic % ofnickel (Ni was used as the raw material alloy 1091, to there by obtain aplurality of electrophotographic light receiving members and a testsample.

Evaluation

As for each of the electrophotographic light receiving members obtainedin Experiment 1 and Comparative Experiments 1 to 5, the content of eachmetal atoms contained in the light receiving layer was examined bysubjecting the light receiving layer to analysis using a commerciallyavailable SIMS (a secondary ion mass spectrometer IMS-3F, produced byCAMEKA Company). The results obtained are collectively shown in Table 2.

Each of the electrophotographic light receiving members obtained inExperiment 1 and Comparative Experiments 1 to 5 was evaluated withrespect to resistance to light-induced fatigue in the following manner.That is, as for each electrophotographic light receiving member,semiconductor laser of 785 nm in luminous wavelength and 10 mW in outputpower was continuously irradiated to its central region of about 3 cm indiameter for 24 hours while rotating the electrophotographic lightreceiving member.

Then, the electrophotographic light receiving member was set to amodification of the electrophotographic copying machine NP-9330 producedby CANON Kabushiki Kaisha for experimental purposes, and it wasevaluated with respect to its electrophotographic characteristics. Thatis, using a A3-sized test chart having, in the lengthwise direction, asolid black area of 1.1 in reflection density extending from one endside to the 4 cm distant position from the end side, a solid white areaof 0.08 in reflection density extending from the 4 cm distant positionto the 8 cm distant position respectively from the end side, and theremaining halftone area of 0.3 in reflection density, reproduction wasconducted on a A3-sized white paper under conditions of providing areproduced image with a standard image density. As for the reproducedimage obtained, there was examined a difference between the imagereproduced at the central region irradiated with the semiconductor laserof the electrophotographic light receiving member and the imagereproduced at the remaining region of the electrophotographic lightreceiving member in terms of density. That is, as for the reproducedimage obtained, the ratio between the reflection density of the areaextending from the 4 cm distant position to the 8 cm distant positionrespectively from the end position of the paper (corresponding to thesolid black area of the test chart) and the reflection density of thearea extending from the 4 cm distant position from the end position tothe end position (corresponding to the solid white area of the testchart) was examined by means of a conventional reflection densitometer.The examined results are collectively shown in Table 2.

From the results shown in Table 2, it was found that theelectrophotographic light receiving member obtained in Experiment 1 isthe smallest in terms of the reflection density ratio and slight interms of ghost appearance and thus, it is superior in view ofelectrophotographic characteristics.

Further, as for each electrophotographic light receiving member, arubber roller of 40 mm in diameter was contacted thereto, and a sinewave voltage of 700 V was applied for an hour while rotating theelectrophotographic light receiving member and the rubber roller. Then,the electrophotographic light receiving member was set to the foregoingelectrophotographic copying machine, wherein it was subjected to imagereproduction, using a solid black test chart. The image obtained wasevaluated in comparison with the image obtained using theelectrophotographic light receiving member before having applied theabove voltage in terms of the ratio of white dots appeared. Theevaluated results obtained are collectively shown in Table 2, whereinthe dot appearance ratio of the electrophotographic light receivingmember obtained in Experiment 1 is set at 1.

From the results shown in Table 2, it was found that theelectrophotographic light receiving member obtained in Experiment 1 isthe smallest in terms of the dot appearance ratio and thus, it issuperior in view of electrophotographic characteristics.

Further in addition, as for each electrophotographic light receivingmember, evaluation was conducted with respect to charge mobility inaccordance with the time-of-flight method. The evaluated resultsobtained are collectively shown in Table 2, wherein the charge mobilityof the electrophotographic light receiving member obtained in Experiment1 is set at 1.

From the results shown in Table 2, it was found that theelectrophotographic light receiving member obtained in Experiment 1 isthe fastest in terms of charge mobility and thus, it is superior in viewof electrophotographic characteristics.

Further more, using each of the test samples obtained in Experiment 1and Comparative Experiments 1 to 5, the correspondingelectrophotographic light receiving member was evaluated with respect tototal spin density by the ESR. The evaluated results obtained arecollectively shown in Table 2, wherein the values shown are valuesrelative to the total spin density of the electrophotographic lightreceiving member obtained in Experiment 1 which is set at 1. From theresults shown in Table 2, it was found that the electrophotographiclight receiving member obtained in Experiment 1 is the smallest in termsof the total spin density and thus, it is superior in view ofelectrophotographic characteristics.

As apparent from the above results, it was found that theelectrophotographic light receiving member obtained in Experiment 1 issurpassing other electrophotographic light receiving members obtained inComparative Experiments 1 to 5.

Experiment 2 and Comparative Experiment 6

Experiment 2

The procedures of Experiment 1 were repeated, except that thecomposition ratio of the silicon (Si), chromium (Cr), iron (Fe),magnesium (Mg), sodium (Na), and nickel (Ni) by which the raw materialalloy 1091 is constituted was changed to two different compositionratios shown in Table 3, to thereby obtain a plurality ofelectrophotographic light receiving members as for each raw materialalloy, and a test sample as for each raw material alloy.

Comparative Experiment 6

The procedures of Experiment 1 were repeated, except that thecomposition ratio of the silicon (Si), chromium (Cr), iron (Fe),magnesium (Mg), sodium (Na), and nickel (Ni) by which the raw materialalloy 1091 is constituted was changed to two different compositionratios shown in Table 3, to thereby obtain a plurality ofelectrophotographic light receiving members as for each raw materialalloy, and a test sample as for each raw material alloy.

Evaluation

As for each of the electrophotographic light receiving members obtainedin Experiment 2 and Comparative Experiment 6, the content of each metalatoms contained in the light receiving layer was examined by subjectingthe light receiving layer to analysis using the SIMS as well as inExperiment 1. The results obtained are collectively shown in Table 4.

As for each of the electrophotographic light receiving members and thetest samples obtained in Experiment 2 and Comparative Experiment 6,evaluation was conducted in the same manner as in Experiment 1. Theevaluated results obtained are collectively shown in Table 4.

From the results shown in Table 4, it was found that any of the lightreceiving members having a light receiving layer containing the fivekinds of metal atoms respectively in an amount of less than 0.9 atomicppm is superior in terms of the electrophotographic characteristicsrequired for an electrophotographic light receiving member.

Experiment 3

In accordance with the foregoing film-forming manner using the apparatusshown in FIG. 4 and under the conditions shown in Table 5, there wereprepared a plurality of electrophotographic light receiving members anda test sample, wherein as the substrate, there was used a cylindricalaluminum substrate of 108 mm in outer diameter.

As for one of the electrophotographic light receiving members obtained,the content of each metal atoms contained in the light receiving layerwas examined by subjecting the light receiving layer to analysis usingthe SIMS as well as in Experiment 1. The result obtained is shown inTable 6.

As for the remaining electrophotographic light receiving members and thetest sample, evaluation was conducted in the same manner as inExperiment 1. The evaluated results obtained are collectively shown inTable 6.

From the results shown in Table 6, it was found that the light receivingmember obtained in this experiment excels in electrophotographiccharacteristics as well as the electrophotographic light receivingmember obtained in Experiment 1.

Experiment 4 and Comparative Experiments 7 to 11

Experiment 4

Firstly, there was provided, as the substrate, an aluminum plate of 1 mmin thickness and 4 cm×4 cm in size and having a polished surface of 0.5s. This aluminum plate was subjected to ultrasonic cleaning using1,1,1-trichloroethane for 10 minutes. Using the aluminum plate as thesubstrate, there was prepared a solar cell in accordance with theforegoing solar cell-preparing manner using the apparatus shown in FIG.5 under the conditions shown in Table 7, wherein the film formation wasconducted in the chamber I₁. The solar cell was made to have 50translucent light incident side electrodes of 3 mm in diameter, eachcomprising an Au film. Each portion provided with the electrode of 3 mmin diameter was designed such that it could serve as an independentsub-cell (which can be separately dedicated for the measurement of I-Vcharacteristics).

Comparative Experiment 7

The procedures of Experiment 4 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.80 atomic % of silicon (Si) and 0.20 atomic % of chromium (Cr), tothereby obtain a solar cell.

Comparative Experiment 8

The procedures of Experiment 4 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.80 atomic % of silicon (Si) and 0.20 atomic % of iron (Fe), tothereby obtain a solar cell.

Comparative Experiment 9

The procedures of Experiment 4 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.65 atomic % of silicon (Si) and 0.35 atomic % of magnesium (Mg), tothereby obtain a solar cell.

Comparative Experiment 10

The procedures of Experiment 4 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.65 atomic % of silicon (Si) and 0.35 atomic % of sodium (Na), tothereby obtain a solar cell.

Comparative Experiment 11

The procedures of Experiment 4 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.80 atomic % of silicon (Si) and 0.20 atomic % of nickel (Ni), tothereby obtain a solar cell.

Evaluation

As for each of the solar cells obtained in Experiment 4 and ComparativeExperiments 7 to 11, a part of which was cut to obtain a measuringsample. Each measuring sample was subjected to analysis by the SIMS aswell as in the foregoing case of the electrophotographic light receivingmember to examine the content of each metal atoms. The results obtainedare collectively shown in Table 8.

Then, as for each of the solar cells obtained in Experiment 4 andComparative Experiments 7 to 11, each sub-cell was subjected tomeasurement of the I-V characteristics under a solar cell simulator.Based on the measured results, there were obtained a survival rate (theproportion of the number of non-shortcircuited sub-cells among the 50sub-cells) and an external quantum efficiency (the ratio to a mean valuebetween the maximum value and the minimum value for the survivedsub-cells with respect to external quantum efficiency). Successively, asfor each of the survived sub-cells, semiconductor laser of 785 nm inluminous wavelength and 10 mW in output power was continuouslyirradiated for 78 hours, the efficiency was examined, and based on theexamined results, there was obtained a mean efficiency retention rate(the change of rate between the initial efficiency and the efficiencyafter having subjected to the semiconductor laser irradiation wasexpressed by a percentage value). The results obtained are collectivelyshown in Table 8.

From the results shown in Table 8, it was found that the solar cellobtained in Experiment 4 surpasses any of the solar cells obtained inComparative Experiments 7 to 11 in terms of the solar cellcharacteristic.

Experiment 5 and Comparative Experiments 12 to 16

Experiment 5

In accordance with the foregoing film-forming manner using the apparatusshown in FIG. 6 and under the conditions shown in Table 9, there wereprepared a plurality of electrophotographic light receiving members,wherein as the substrate, there was used a cylindrical aluminumsubstrate of 108 mm in outer diameter and having a mirror ground surfacein every case.

In addition, the above film-forming procedures under the conditionsshown in Table 9 were repeated, except that the layer thickness waschanged to 5 μm and a quartz plate was used as the substrate, to therebyobtain a test sample having the same layer as in the above.

Comparative Experiment 12

The procedures of Experiment 5 were repeated, except that a raw materialalloy composed of 99.80 atomic % of silicon (Si) and 0.20 atomic % ofchromium (Cr) was used as the raw material alloy 1091, to thereby obtaina plurality of electrophotographic light receiving members and a testsample.

Comparative Experiment 13

The procedures of Experiment 5 were repeated, except that a raw materialalloy composed of 99.80 atomic % of silicon (Si) and 0.20 atomic % ofiron (Fe) was used as the raw material alloy 1091, to thereby obtain aplurality of electrophotographic light receiving members and a testsample.

Comparative Experiment 14

The procedures of Experiment 5 were repeated, except that a raw materialalloy composed of 99.65 atomic % of silicon (Si) and 0.35 atomic % ofmagnesium (Mg) was used as the raw material alloy 1091, to therebyobtain a plurality of electrophotographic light receiving members and atest sample.

Comparative Experiment 15

The procedures of Experiment 5 were repeated, except that a raw materialalloy composed of 99.65 atomic % of silicon (Si) and 0.35 atomic % ofsodium (Na was used as the raw material alloy 1091, to thereby obtain aplurality of electrophotographic light receiving members and a testsample.

Comparative Experiment 16

The procedures of Experiment 5 were repeated, except that a raw materialalloy composed of 99.80 atomic % of silicon (Si) and 0.20 atomic % ofnickel (Ni) was used as the raw material alloy 1091, to thereby obtain aplurality of electrophotographic light receiving members and a testsample.

Evaluation

As for each of the electrophotographic light receiving members obtainedin Experiment 5 and Comparative Experiments 12 to 16, the content ofeach metal atoms contained in the light receiving layer was examined bysubjecting the light receiving layer to analysis using the SIMS used inExperiment 1. The results obtained are collectively shown in Table 10.

Each of the electrophotographic light receiving members obtained inExperiment 5 and Comparative Experiments 12 to 16 was evaluated withrespect to resistance to light-induced fatigue in the following manner.That is, as for each electrophotographic light receiving member,semiconductor laser of 785 nm in luminous wavelength and 10 mW in outputpower was continuously irradiated to its central region of about 3 cm indiameter for 24 hours while rotating the electrophotographic lightreceiving member.

Then, the electrophotographic light receiving member was set to amodification of the electrophotographic copying machine NP-9330 producedby CANON Kabushiki Kaisha for experimental purposes, and it wasevaluated in the same manner as in Experiment 1. The evaluated resultsobtained are collectively shown in Table 10.

From the results shown in Table 10, it was found that theelectrophotographic light receiving member obtained in Experiment 5 isthe smallest in terms of the reflection density ratio and slight interms of ghost appearance and thus, it is superior in view ofelectrophotographic characteristics.

Further, as for each electrophotographic light receiving member, arubber roller of 40 mm in diameter was contacted thereof and a sine wavevoltage of 700 V was applied for an hour while rotating theelectrophotographic light receiving member and the rubber roller as wellas in the case of Experiment 1. Then, the electrophotographic lightreceiving member was set to the foregoing electrophotographic copyingmachine, wherein it was subjected to image reproduction, using a solidblack test chart. The image obtained was evaluated in comparison withthe image obtained using the electrophotographic light receiving memberbefore having applied the above voltage in terms of the ratio of whitedots appeared. The evaluated results obtained are collectively shown inTable 10.

From the results shown in Table 10, it was found that theelectrophotographic light receiving member obtained in Experiment 5 isthe smallest in terms of the dot appearance ratio and thus, it issuperior in view of electrophotographic characteristics.

Further in addition, as for each electrophotographic light receivingmember, evaluation was conducted with respect to charge mobility inaccordance with the time-of-flight method. The evaluated resultsobtained are collectively shown in Table 10, wherein the charge mobilityof the electrophotographic light receiving member obtained in Experiment5 is set at 1.

From the results shown in Table 10, it was found that theelectrophotographic light receiving member obtained in Experiment 5 isthe fastest in terms of charge mobility and thus, it is superior in viewof electrophotographic characteristics.

Further more, using each of the test samples obtained in Experiment 5and Comparative Experiments 12 to 16, the correspondingelectrophotographic light receiving member was evaluated with respect tototal spin density by the ESR. The evaluated results obtained arecollectively shown in Table 10, wherein the values shown are valuesrelative to the total spin density of the electrophotographic lightreceiving member obtained in Experiment 5 which is set at 1. From theresults shown in Table 10, it was found that the electrophotographiclight receiving member obtained in Experiment 5 is the smallest in termsof the total spin density and thus, it is superior in view ofelectrophotographic characteristics.

As apparent from the above results, it was found that theelectrophotographic light receiving member obtained in Experiment 5 issurpassing other electrophotographic light receiving members obtained inComparative Experiments 12 to 16.

Experiment 6 and Comparative Experiment 17

Experiment 6

The procedures of Experiment 5 were repeated, except that thecomposition ratio of the silicon (Si), chromium (Cr), iron (Fe),magnesium (Mg), sodium (Na), and nickel (Ni) by which the raw materialalloy 1091 is constituted was changed to two different compositionratios shown in Table 11, to thereby obtain a plurality ofelectrophotographic light receiving members as for each raw materialalloy, and a test sample as for each raw material alloy.

Comparative Experiment 17

The procedures of Experiment 5 were repeated, except that thecomposition ratio of the silicon (Si), chromium (Cr), iron (Fe),magnesium (Mg), sodium (Na), and nickel (Ni) by which the raw materialalloy 1091 is constituted was changed to two different compositionratios shown in Table 11, to thereby obtain a plurality ofelectrophotographic light receiving members as for each raw materialalloy, and a test sample as for each raw material alloy.

Evaluation

As for each of the electrophotographic light receiving members obtainedin Experiment 6 and Comparative Experiment 17, the content of each metalatoms contained in the light receiving layer was examined by subjectingthe light receiving layer to analysis using the SIMS used inExperiment 1. The results obtained are collectively shown in Table 12.

As for each of the electrophotographic light receiving members and thetest samples obtained in Experiment 6 and Comparative Experiment 17,evaluation was conducted in the same manner as in Experiment 1. Theevaluated results obtained are collectively shown in Table 12.

From the results shown in Table 12, it was found that any of the lightreceiving members having a light receiving layer containing the fivekinds of metal atoms respectively in an amount of less than 0.9 atomicppm is superior in terms of the electrophotographic characteristicsrequired for an electrophotographic light receiving member.

Experiment 7

In accordance with the foregoing film-forming manner using the apparatusshown in FIG. 8 and under the conditions shown in Table 13, there wereprepared a plurality of electrophotographic light receiving members anda test sample, wherein as the substrate, there was used a cylindricalaluminum substrate of 108 mm in outer diameter.

As for one of the electrophotographic light receiving members obtained,the content of each metal atoms contained in the light receiving layerwas examined by subjecting the light receiving layer to analysis usingthe SIMS used in Experiment 1. The result obtained is shown in Table 14.

As for the remaining electrophotographic light receiving members and thetest sample, evaluation was conducted in the same manner as inExperiment 1. The evaluated results obtained are collectively shown inTable 14.

From the results shown in Table 14, it was found that the lightreceiving member obtained in this experiment excels inelectrophotographic characteristics as well as the electrophotographiclight receiving member obtained in Experiment 5.

Experiment 8 and Comparative Experiments 18 to 22

Experiment 8

Firstly, there was provided, as the substrate, an aluminum plate of 1 mmin thickness and 4 cm×4 cm in size and having a polished surface of 0.2s. This aluminum plate was subjected to ultrasonic cleaning using1,1,1-trichloroethane for 10 minutes. Using the aluminum plate as thesubstrate, there was prepared a Shottky type solar cell in accordancewith the foregoing solar cell-preparing manner using the apparatus shownin FIG. 5 under the conditions shown in Table 15, wherein the filmformation was conducted in the chamber I₁. The solar cell was made tohave 50 translucent light incident side electrodes of 3 mm in diameter,each comprising an Au film. Each portion provided with the electrode of3 mm in diameter was designed such that it could serve as an independentsub-cell (which can be separately dedicated for the measurement of I-Vcharacteristics).

Comparative Experiment 18

The procedures of Experiment 8 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.80 atomic % of silicon (Si) and 0.20 atomic % of chromium (Cr), tothereby obtain a solar cell.

Comparative Experiment 19

The procedures of Experiment 8 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.80 atomic % of silicon (Si) and 0.20 atomic % of iron (Fe), tothereby obtain a solar cell.

Comparative Experiment 20

The procedures of Experiment 8 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.65 atomic % of silicon (Si) and 0.35 atomic % of magnesium (Mg), tothereby obtain a solar cell.

Comparative Experiment 21

The procedures of Experiment 8 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.65 atomic % of silicon (Si) and 0.35 atomic % of sodium (Na), tothereby obtain a solar cell.

Comparative Experiment 22

The procedures of Experiment 8 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.80 atomic % of silicon (Si) and 0.20 atomic % of nickel (Ni), tothereby obtain a solar cell.

Evaluation

As for each of the solar cells obtained in Experiment 8 and ComparativeExperiments 18 to 22, a part of which was cut to obtain a measuringsample. Each measuring sample was subjected to analysis by the SIMS aswell as in the foregoing case of the electrophotographic light receivingmember to examine the content of each metal atoms. The results obtainedare collectively shown in Table 16.

Then, as for each of the solar cells obtained in Experiment 8 andComparative Experiments 18 to 22, each sub-cell was subjected tomeasurement of the I-V characteristics under a solar cell simulator.Based on the measured results, there were obtained a survival rate (theproportion of the number of non-shortcircuited sub-cells among the 50sub-cells) and an external quantum efficiency (the ratio to a mean valuebetween the maximum value and the minimum value for the survivedsub-cells with respect to external quantum efficiency). Successively, asfor each of the survived sub-cells, semiconductor laser of 785 nm inluminous wavelength and 10 mW in output power was irradiated for 78hours, the efficiency was examined, and based on the examined results,there was obtained a mean efficiency retention rate (the change of ratebetween the initial efficiency and the efficiency after having subjectedto the semiconductor laser irradiation was expressed by a percentagevalue). The results obtained are collectively shown in Table 16.

From the results obtained in the above it was found that the solar cellobtained in Experiment 8 is surpassing any of the solar cells obtainedin Comparative Experiments 18 to 22 in terms of the solar cellcharacteristic.

Experiment 9 and Comparative Experiments 23 to 27

Experiment 9

Firstly, there was provided, as the substrate, an aluminum plate of 1 mmin thickness and 4 cm×4 cm in size and having a polished surface of 0.2s. This aluminum plate was subjected to ultrasonic cleaning using1,1,1-trichloroethane for 10 minutes. Using the aluminum plate as thesubstrate, there was prepared a pin junction type solar cell inaccordance with the foregoing solar cell-preparing manner using theapparatus shown in FIG. 5 under the conditions shown in Table 17,wherein the film formation was conducted successively in the chamber N,in chamber I₁ and then in the chamber P. The solar cell was made to have50 translucent light incident side electrodes of 3 mm in diameter eachcomprising an ITO film and having a cross-like shaped Ag grid of 0.3 mmin width. Each portion provided with the electrode of 3 mm in diameterwas designed such that it could serve as an independent sub-cell (whichcan be separately dedicated for the measurement of I-V characteristics).

Comparative Experiment 23

The procedures of Experiment 9 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.80 atomic % of silicon (Si) and 0.20 atomic % of chromium (Cr), tothereby obtain a solar cell.

Comparative Experiment 24

The procedures of Experiment 9 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.80 atomic % of silicon (Si and 0.20 atomic % of iron (Fe), to therebyobtain a solar cell.

Comparative Experiment 25

The procedures of Experiment 9 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.65 atomic % of silicon (Si) and 0.35 atomic % of magnesium (Mg), tothereby obtain a solar cell.

Comparative Experiment 26

The procedures of Experiment 9 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.65 atomic % of silicon (Si and 0.35 atomic % of sodium (Na), tothereby obtain a solar cell.

Comparative Experiment 27

The procedures of Experiment 9 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.80 atomic % of silicon (Si) and 0.20 atomic % of nickel (Ni), tothereby obtain a solar cell.

Evaluation

As for each of the solar cells obtained in Experiment 9 and ComparativeExperiments 23 to 27, a part of which was cut to obtain a measuringsample. Each measuring sample was subjected to analysis by the SIMS aswell as in the foregoing case of the electrophotographic light receivingmember to examine the content of each metal atoms. The results obtainedare collectively shown in Table 18.

Then, as for each of the solar cells obtained in Experiment 9 andComparative Experiments 23 to 27, each sub-cell was subjected tomeasurement of the I-V characteristics under a solar cell simulator.Based on the measured results, there were obtained a survival rate (theproportion of the number of non-shortcircuited sub-cells among the 50sub-cells) and an external quantum efficiency (the ratio to a mean valuebetween the maximum value and the minimum value for the survivedsub-cells with respect to external quantum efficiency). Successively, asfor each of the survived sub-cells, semiconductor laser of 785 nm inluminous wavelength and 10 mW in output power was continuouslyirradiated for 78 hours, the efficiency was examined, and based on theexamined results, there was obtained a mean efficiency retention rate(the change of rate between the initial efficiency and the efficiencyafter having subjected to the semiconductor laser irradiation wasexpressed by a percentage value). The results obtained are collectivelyshown in Table 18.

From the results obtained in the above, it was found that the solar cellobtained in Experiment 9 is surpassing any of the solar cells obtainedin Comparative Experiments 23 to 27 in terms of the solar cellcharacteristic.

Experiment 10 and Comparative Experiments 28 to 32

Experiment 10

In accordance with the foregoing film-forming manner using the apparatusshown in FIG. 6 and under the conditions shown in Table 19, there wereprepared a plurality of electrophotographic light receiving members eachhaving a two-layered light receiving layer, wherein as the substrate,there was used a cylindrical aluminum substrate of 108 mm in outerdiameter and having a mirror ground surface in every case.

In addition, the above film-forming procedures under the conditions forthe formation of the second layer shown in Table 19 were repeated,except that the layer thickness was changed to 5 μm and a quartz platewas used as the substrate, to thereby obtain a test sample.

Comparative Experiment 28

The procedures of Experiment 10 were repeated, except that a rawmaterial alloy composed of 99.80 atomic % of silicon (Si) and 0.20atomic % of chromium (Cr) was used as the raw material alloy 1091, tothere by obtain a plurality of electrophotographic light receivingmembers and a test sample.

Comparative Experiment 29

The procedures of Experiment 10 were repeated, except that a rawmaterial alloy composed of 99.80 atomic % of silicon (Si) and 0.20atomic % of iron (Fe) was used as the raw material alloy 1091, to thereby obtain a plurality of electrophotographic light receiving members anda test sample.

Comparative Experiment 30

The procedures of Experiment 10 were repeated, except that a rawmaterial alloy composed of 99.65 atomic % of silicon (Si) and 0.35atomic % of magnesium (Mg) was used as the raw material alloy 1091, tothere by obtain a plurality of electrophotographic light receivingmembers and a test sample.

Comparative Experiment 31

The procedures of Experiment 10 were repeated, except that a rawmaterial alloy composed of 99.65 atomic % of silicon (Si) and 0.35atomic % of sodium (Na) was used as the raw material alloy 1091, tothere by obtain a plurality of electrophotographic light receivingmembers and a test sample.

Comparative Experiment 32

The procedures of Experiment 10 were repeated, except that a rawmaterial alloy composed of 99.80 atomic % of silicon (Si) and 0.20atomic % of nickel (Ni) was used as the raw material alloy 1091, tothere by obtain a plurality of electrophotographic light receivingmembers and a test sample.

Evaluation

As for each of the electrophotographic light receiving members obtainedin Experiment 10 and Comparative Experiments 28 to 32, the content ofeach metal atoms contained in the second layer was examined bysubjecting the light receiving layer to analysis using the SIMS. Theresults obtained are collectively shown in Table 20.

Each of the electrophotographic light receiving members obtained inExperiment 10 and Comparative Experiments 28 to 32 was evaluated withrespect to resistance to light-induced fatigue in the following manner.That is, as for each electrophotographic light receiving member,semiconductor laser of 785 nm in luminous wavelength and 10 mW in outputpower was continuously irradiated to its central region of about 3 cm indiameter for 24 hours while rotating the electrophotographic lightreceiving member.

Then, the electrophotographic light receiving member was set to amodification of the electrophotographic copying machine NP-9330 producedby CANON Kabushiki Kaisha for experimental purposes, and it wasevaluated with respect to its electrophotographic characteristics. Thatis, using a A3-sized test chart having, in the lengthwise direction, asolid black area of 1.1 in reflection density extending from one endside to the 4 cm distant position from the end side, a solid white areaof 0.08 in reflection density extending from the 4 cm distant positionto the 8 cm distant position respectively from the end side, and theremaining halftone area of 0.3 in reflection density, reproduction wasconducted on a A3-sized white paper under conditions of providing areproduced image with a standard image density. As for the reproducedimage obtained, there was examined a difference between the imagereproduced at the central region irradiated with the semiconductor laserof the electrophotographic light receiving member and the imagereproduced at the remaining region of the electrophotographic lightreceiving member in terms of density. That is, as for the reproducedimage obtained, the ratio between the reflection density of the areaextending from the 4 cm distant position to the 8 cm distant positionrespectively from the end position of the paper (corresponding to thesolid black area of the test chart) and the reflection density of thearea extending from the 4 cm distant position from the end position tothe end position (corresponding to the solid white area of the testchart) was examined by means of a conventional reflection densitometer.The examined results are collectively shown in Table 20.

From the results shown in Table 20, it was found that theelectrophotographic light receiving member obtained in Experiment 10 isthe smallest in terms of the reflection density ratio and slight interms of ghost appearance and thus, it is superior in view ofelectrophotographic characteristics.

Further, as for each electrophotographic light receiving member, arubber roller of 40 mm in diameter was contacted thereto, and a sinewave voltage of 700 V was applied for an hour while rotating theelectrophotographic light receiving member and the rubber roller. Then,the electrophotographic light receiving member was set to the foregoingelectrophotographic copying machine, wherein it was subjected to imagereproduction, using a solid black test chart. The image obtained wasevaluated in comparison with the image obtained using theelectrophotographic light receiving member before having applied theabove voltage in terms of the ratio of white dots appeared. Theevaluated results obtained are collectively shown in Table 20, whereinthe dot appearance ratio of the electrophotographic light receivingmember obtained in Experiment 10 is set at 1.

From the results shown in Table 20, it was found that theelectrophotographic light receiving member obtained in Experiment 10 isthe smallest in terms of the dot appearance ratio and thus, it issuperior in view of electrophotographic characteristics.

Further in addition, as for each electrophotographic light receivingmember, evaluation was conducted with respect to charge mobility inaccordance with the time-of-flight method. The evaluated resultsobtained are collectively shown in Table 20, wherein the charge mobilityof the electrophotographic light receiving member obtained in Experiment10 is set at 1.

From the results shown in Table 20, it was found that theelectrophotographic light receiving member obtained in Experiment 10 isthe fastest in terms of charge mobility and thus, it is superior in viewof electrophotographic characteristics.

Further more, using each of the test samples obtained in Experiment 10and Comparative Experiments 28 to 32, the correspondingelectrophotographic light receiving member was evaluated with respect tototal spin density by the ESR. The evaluated results obtained arecollectively shown in Table 20, wherein the values shown are valuesrelative to the total spin density of the electrophotographic lightreceiving member obtained in Experiment 10 which is set at 1. From theresults shown in Table 20, it was found that the electrophotographiclight receiving member obtained in Experiment 10 is the smallest interms of the total spin density and thus, it is superior in view ofelectrophotographic characteristics.

As apparent from the above results, it was found that theelectrophotographic light receiving member obtained in Experiment 10 issurpassing other electrophotographic light receiving members obtained inComparative Experiments 28 to 32.

Experiment 11 and Comparative Experiment 33

Experiment 11

The procedures of Experiment 10 were repeated, except that thecomposition ratio of the silicon (Si), chromium (Cr), iron (Fe),magnesium (Mg), sodium (Na), and nickel (Ni) by which the raw materialalloy 1091 is constituted was changed to two different compositionratios shown in Table 21, to thereby obtain a plurality ofelectrophotographic light receiving members each having a two-layeredlight receiving layer as for each raw material alloy, and a test sampleas for each raw material alloy.

Comparative Experiment 33

The procedures of Experiment 10 were repeated, except that thecomposition ratio of the silicon (Si), chromium (Cr), iron (Fe),magnesium (Mg), sodium (Na), and nickel (Ni) by which the raw materialalloy 1091 is constituted was changed to two different compositionratios shown in Table 21, to thereby obtain a plurality ofelectrophotographic light receiving members as for each raw materialalloy, and a test sample as for each raw material alloy.

Evaluation

As for each of the electrophotographic light receiving members obtainedin Experiment 11 and Comparative Experiment 33, the content of eachmetal atoms contained in the second layer was examined by subjecting thelight receiving layer to analysis using the SIMS as well as inExperiment 10. The results obtained are collectively shown in Table 22.

As for each of the electrophotographic light receiving members and thetest samples obtained in Experiment 11 and Comparative Experiment 33,evaluation was conducted in the same manner as in Experiment 10. Theevaluated results obtained are collectively shown in Table 22.

From the results shown in Table 22, it was found that any of the lightreceiving members having a two layered light receiving layer containingthe five kinds of metal atoms respectively in an amount of less than 0.9atomic ppm is superior in terms of the electrophotographiccharacteristics required for an electrophotographic light receivingmember.

Experiment 12

In accordance with the foregoing film-forming manner using the apparatusshown in FIG. 8 and under the conditions shown in Table 23, there wereprepared a plurality of electrophotographic light receiving members eachhaving a two-layered light receiving layer and a test sample. As thesubstrate for each electrophotographic light receiving member, there wasused a cylindrical aluminum substrate of 108 mm in outer diameter.

As for one of the electrophotographic light receiving members obtained,the content of each metal atoms contained in the second layer wasexamined by subjecting the light receiving layer to analysis using theSIMS. The result obtained is shown in Table 24.

As for the remaining electrophotographic light receiving members and thetest sample, evaluation was conducted in the same manner as inExperiment 10. The evaluated results obtained are collectively shown inTable 24.

From the results shown in Table 24, it was found that the lightreceiving member obtained in this experiment excels inelectrophotographic characteristics as well as the electrophotographiclight receiving member obtained in Experiment 10.

Experiment 13 and Comparative Experiments 34 to 38

Experiment 13

Firstly, there was provided, as the substrate, an aluminum plate of 1 mmin thickness and 4 cm×4 cm in size and having a polished surface of 0.5s. This aluminum plate was subjected to ultrasonic cleaning using1,1,1-trichloroethane for 10 minutes. Using the aluminum plate as thesubstrate, there was prepared a pin junction type solar cell inaccordance with the foregoing solar cell-preparing manner using theapparatus shown in FIG. 5 under the conditions shown in Table 25,wherein the film formation was conducted successively in the chamber N,in the chamber I₁ and in the chamber P. The solar cell was made to have50 translucent light incident side electrodes of 3 mm in diameter eachcomprising an ITO film and having a cross-like like shaped Ag grid of0.3 mm in width. Each portion provided with the electrode of 3 mm indiameter was designed such that it could serve as an independentsub-cell (which can be separately dedicated for the measurement of I-Vcharacteristics).

Comparative Experiment 34

The procedures of Experiment 13 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.80 atomic % of silicon (Si) and 0.20 atomic % of chromium (Cr), tothereby obtain a solar cell.

Comparative Experiment 35

The procedures of Experiment 13 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.80 atomic % of silicon (Si) and 0.20 atomic % of iron (Fe), tothereby obtain a solar cell.

Comparative Experiment 36

The procedures of Experiment 13 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.65 atomic % of silicon (Si) and 0.35 atomic % of magnesium (MW), tothereby obtain a solar cell.

Comparative Experiment 37

The procedures of Experiment 13 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.65 atomic % of silicon (Si) and 0.35 atomic % of sodium (Na), tothereby obtain a solar cell.

Comparative Experiment 38

The procedures of Experiment 13 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.80 atomic % of silicon (Si) and 0.20 atomic % of nickel (Ni), tothereby obtain a solar cell.

Evaluation

As for each of the solar cells obtained in Experiment 13 and ComparativeExperiments 34 to 38, a part of which was cut to obtain a measuringsample. Each measuring sample was subjected to analysis by the SIMS aswell as in the foregoing case of the electrophotographic light receivingmember to examine the content of each metal atoms. The results obtainedare collectively shown in Table 26.

Then, as for each of the solar cells obtained in Experiment 13 andComparative Experiments 34 to 38, each sub-cell was subjected tomeasurement of the I-V characteristics under a solar cell simulator.Based on the measured results, there were obtained a survival rate (theproportion of the number of non-shortcircuited sub-cells among the 50sub-cells) and an external quantum efficiency (the ratio to a mean valuebetween the maximum value and the minimum value for the survivedsub-cells with respect to external quantum efficiency). Successively, asfor each of the survived sub-cells, semiconductor laser of 785 nm inluminous wavelength and 10 mW in output power was continuouslyirradiated for 78 hours, the efficiency was examined, and based on theexamined results, there was obtained a mean efficiency retention rate(the change of rate between the initial efficiency and the efficiencyafter having subjected to the semiconductor laser irradiation wasexpressed by a percentage value). The results obtained are collectivelyshown in Table 26.

From the results shown in Table 26, it was found that the solar cellobtained in Experiment 13 is surpassing any of the solar cells obtainedin Comparative Experiments 34 to 38 in terms of the solar cellcharacteristic.

Experiment 14 and Comparative Experiments 39 to 43

Experiment 14

In accordance with the foregoing film-forming manner using the apparatusshown in FIG. 6 and under the conditions shown in Table 27, there wereprepared a plurality of electrophotographic light receiving members eachhaving a two-layered light receiving layer, wherein as the substrate,there was used a cylindrical aluminum substrate of 80 mm in outerdiameter and having an uneven surface shape provided with irregularitiescomposed of a plurality of spherical dimples which had been formed inaccordance with the manner described in Japanese Unexamined PatentPublication No. 231561/1986 in every case.

In addition, the above film-forming procedures under the conditions forthe formation of the second layer shown in Table 27 were repeated,except that the layer thickness was changed to 5 um and a quartz platewas used as the substrate, to thereby obtain a test sample.

Comparative Experiment 39

The procedures of Experiment 14 were repeated, except that a rawmaterial alloy composed of 99.80 atomic % of silicon (Si) and 0.20atomic % of chromium (Cr) was used as the raw material alloy 1091, tothereby obtain a plurality of electrophotographic light receivingmembers and a test sample.

Comparative Experiment 40

The procedures of Experiment 14 were repeated, except that a rawmaterial alloy composed of 99.80 atomic % of silicon (Si) and 0.20atomic % of iron (Fe) was used as the raw material alloy 1091, tothereby obtain a plurality of electrophotographic light receivingmembers and a test sample.

Comparative Experiment 41

The procedures of Experiment 14 were repeated, except that a rawmaterial alloy composed of 99.65 atomic % of silicon (Si) and 0.35atomic % of magnesium (Mg) was used as the raw material alloy 1091, tothereby obtain a plurality of electrophotographic light receivingmembers and a test sample.

Comparative Experiment 42

The procedures of Experiment 14 were repeated, except that a rawmaterial alloy composed of 99.65 atomic % of silicon (Si) and 0.35atomic % of sodium (Na) was used as the raw material alloy 1091, tothereby obtain a plurality of electrophotographic light receivingmembers and a test sample.

Comparative Experiment 43

The procedures of Experiment 14 were repeated, except that a rawmaterial alloy composed of 99.80 atomic % of silicon (Si) and 0.20atomic % of nickel (Ni) was used as the raw material alloy 1091, tothereby obtain a plurality of electrophotographic light receivingmembers and a test sample.

Evaluation

As for each of the electrophotographic light receiving members obtainedin Experiment 14 and Comparative Experiments 39 to 43, the content ofeach metal atoms contained in the second layer was examined bysubjecting the light receiving layer to analysis using the SIMS. Theresults obtained are collectively shown in Table 28.

Each of the electrophotographic light receiving members obtained inExperiment 14 and Comparative Experiments 39 to 43 was evaluated withrespect to resistance to light-induced fatigue in the following manner.That is, as for each electrophotographic light receiving member,semiconductor laser of 785 nm in luminous wavelength and 10 mW in outputpower was continuously irradiated to its central region of about 3 cm indiameter for 24 hours while rotating the electrophotographic lightreceiving member.

Then, the electrophotographic light receiving member was set to amodification of the electrophotographic copying machine NP-9330 producedby CANON Kabushiki Kaisha for experimental purposes, and it wasevaluated in the same manner as in Experiment 1. The evaluated resultsobtained are collectively shown in Table 28.

From the results shown in Table 28, it was found that theelectrophotographic light receiving member obtained in Experiment 14 isthe smallest in terms of the reflection density ratio and slight interms of ghost appearance and thus, it is superior in view ofelectrophotographic characteristics.

Further, as for each electrophotographic light receiving member, arubber roller of 40 mm in diameter was contacted thereto, and a sinewave voltage of 700 V was applied for an hour while rotating theelectrophotographic light receiving member and the rubber roller. Then,the electrophotographic light receiving member was set to the foregoingelectrophotographic copying machine, wherein it was subjected to imagereproduction, using a solid black test chart. The image obtained wasevaluated in comparison with the image obtained using theelectrophotographic light receiving member before having applied theabove voltage in terms of the ratio of white dots appeared. Theevaluated results obtained are collectively shown in Table 28.

From the results shown in Table 28, it was found that theelectrophotographic light receiving member obtained in Experiment 14 isthe smallest in terms of the dot appearance ratio and thus, it issuperior in view of electrophotographic characteristics.

Further in addition, as for each electrophotographic light receivingmember evaluation was conducted with respect to charge mobility inaccordance with the time-of-flight method. The evaluated resultsobtained are collectively shown in Table 28, wherein the charge mobilityof the electrophotographic light receiving member obtained in Experiment14 is set at 1.

From the results shown in Table 28, it was found that theelectrophotographic light receiving member obtained in Experiment 14 isthe fastest in terms of charge mobility and thus, it is superior in viewof electrophotographic characteristics.

Further more, using each of the test samples obtained in Experiment 14and Comparative Experiments 39 to 43, the correspondingelectrophotographic light receiving member was evaluated with respect tototal spin density by the ESR. The evaluated results obtained arecollectively shown in Table 28, wherein the values shown are valuesrelative to the total spin density of the electrophotographic lightreceiving member obtained in Experiment 14 which is set at 1. From theresults shown in Table 28, it was found that the electrophotographiclight receiving member obtained in Experiment 14 is the smallest interms of the total spin density and thus, it is superior in view ofelectrophotographic characteristics.

As apparent from the above results, it was found that theelectrophotographic light receiving member obtained in Experiment 14 issurpassing other electrophotographic light receiving members obtained inComparative Experiments 39 to 43.

Experiment 15 and Comparative Experiment 44

Experiment 15

The procedures of Experiment 14 were repeated, except that thecomposition ratio of the silicon (Si), chromium (Cr), iron (Fe),magnesium (Mg), sodium (Na), and nickel (Ni) by which the raw materialalloy 1091 is constituted was changed to two different compositionratios shown in Table 29, to thereby obtain a plurality ofelectrophotographic light receiving members each having a two-layeredlight receiving layer as for each raw material alloy, and a test sampleas for each raw material alloy.

Comparative Experiment 44

The procedures of Experiment 14 were repeated, except that thecomposition ratio of the silicon (Si), chromium (Cr), iron (Fe),magnesium (Mg), sodium (Na), and nickel (Ni) by which the raw materialalloy 1091 is constituted was changed to two different compositionratios shown in Table 29, to thereby obtain a plurality ofelectrophotographic light receiving members each having a two-layeredlight receiving layer as for each raw material alloy, and a test sampleas for each raw material alloy.

Evaluation

As for each of the electrophotographic light receiving members obtainedin Experiment 15 and Comparative Experiment 44, the content of eachmetal atoms contained in the second layer was examined by subjecting thelight receiving layer to analysis using the SIMS. The results obtainedare collectively shown in Table 30.

As for each of the electrophotographic light receiving members and thetest samples obtained in Experiment 15 and Comparative Experiment 44,evaluation was conducted in the same manner as in Experiment 14. Theevaluated results obtained are collectively shown in Table 30.

From the results shown in Table 30, it was found that any of the lightreceiving members having a two-layered light receiving layer containingthe five kinds of metal atoms respectively in an amount of less than 0.9atomic ppm is superior in terms of the electrophotographiccharacteristics required for an electrophotographic light receivingmember.

Experiment 16 and Comparative Experiments 45 to 49

Experiment 16

Firstly, there was provided, as the substrate, an aluminum plate of 1 mmin thickness and 4 cm×4 cm in size and having a polished surface of 0.5s. This aluminum plate was subjected to ultrasonic cleaning using1,1,1-trichloroethane for 10 minutes. Using the aluminum plate as thesubstrate, there was prepared a pin junction solar cell in accordancewith the foregoing solar cell-preparing manner using the apparatus shownin FIG. 5 under the conditions shown in Table 31, wherein the filmformation was conducted successively in the chamber N, in the chamberI₁, in the chamber I₂, and in the chamber P. The solar cell was made tohave 50 translucent light incident side electrodes of 3 mm in diametereach comprising an Au film and having a cross-like shaped Ag grid of 0.3mm in width. Each portion provided with the electrode of 3 mm indiameter was designed such that it could serve as an independentsub-cell (which can be separately dedicated for the measurement of I-Vcharacteristics).

Comparative Experiment 45

The procedures of Experiment 16 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.80 atomic % of silicon (Si) and 0.20 atomic % of chromium (Cr), tothereby obtain a solar cell.

Comparative Experiment 46

The procedures of Experiment 16 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.80 atomic % of silicon (Si) and 0.20 atomic % of iron (Fe), tothereby obtain a solar cell.

Comparative Experiment 47

The procedures of Experiment 16 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.65 atomic % of silicon (Si) and 0.35 atomic % of magnesium (Mg), tothereby obtain a solar cell.

Comparative Experiment 48

The procedures of Experiment 16 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.65 atomic % of silicon (Si) and 0.35 atomic % of sodium (Na), tothereby obtain a solar cell.

Comparative Experiment 49

The procedures of Experiment 16 were repeated, except that the rawmaterial alloy 5408 was replaced by a raw material alloy composed of99.80 atomic % of silicon (Si) and 0.20 atomic % of nickel (Ni), tothereby obtain a solar cell.

Evaluation

As for each of the solar cells obtained in Experiment 16 and ComparativeExperiments 45 to 49, a part of which was cut to obtain a measuringsample. Each measuring sample was subjected to analysis by the SIMS toexamine the content of each metal atoms. The results obtained arecollectively shown in Table 32.

Then, as for each of the solar cells obtained in Experiment 16 andComparative Experiments 45 to 49, each sub-cell was subjected tomeasurement of the I-V characteristics under a solar cell simulator.Based on the measured results, there were obtained a survival rate (theproportion of the number of non-shortcircuited sub-cells among the 50sub-cells) and an external quantum efficiency (the ratio to a mean valuebetween the maximum value and the minimum value for the survivedsub-cells with respect to external quantum efficiency). Successively, asfor each of the survived sub-cells, semiconductor laser of 785 nm inluminous wavelength and 10 mW in output power was irradiated for 78hours, the efficiency was examined, and based on the examined results,there was obtained a mean efficiency retention rate (the change of ratebetween the initial efficiency and the efficiency after having subjectedto the semiconductor laser irradiation was expressed by a percentagevalue). The results obtained are collectively shown in Table 32.

From the results obtained in the above, it was found that the solar cellobtained in Experiment 16 is surpassing any of the solar cells obtainedin Comparative Experiments 45 to 49 in terms of the solar cellcharacteristic.

Experiment 17

The procedures of Experiment 1 were repeated, except that as the rawmaterial alloy, five different raw material alloys in which only thecontent of the Cr is different from the raw material alloy used inExperiment 1, to thereby obtain a plurality of electrophotographic lightreceiving members and a test sample as for each raw material alloy. Thecontent of the Cr in each of the five different raw material alloys waschanged to a value of 0.07 atomic %, 0.22 atomic %, 0.2 atomic %, 0.3atomic %, and 0.5 atomic % as shown in Sample Nos. 1 to 5 of Table 33.

As for each of the electrophotographic light receiving members and eachof the test samples, evaluation was conducted in accordance with theevaluation manner described in Example 1. The results obtained arecollectively shown in Table 33.

From the results shown in Table 33, it was found that any of theelectrophotographic light receiving members having a light receivinglayer of less than 0.9 ppm especially in terms of the Cr content issuperior in terms of the electrophotographic characteristics requiredfor an electrophotographic light receiving member.

Experiment 18

The procedures of Experiment 17 were repeated, except that as the rawmaterial alloy, five different raw material alloys in which the contentof the chromium is constant at a fixed value and only the content of theNa is different from each other, to thereby obtain a plurality ofelectrophotographic light receiving members and a test sample as foreach raw material alloy. The content of the Na in each of the fivedifferent raw material alloys was changed to a value of 0.11 atomic %,0.22 atomic %, 0.35 atomic %, 0.5 atomic %, and 0.8 atomic % as shown inSample Nos. 1 to 5 of Table 34.

As for each of the electrophotographic light receiving members and eachof the test samples, evaluation was conducted in accordance with theevaluation manner described in Example 1. The results obtained arecollectively shown in Table 34.

From the results shown in Table 34, it was found that any of theelectrophotographic light receiving members having a light receivinglayer of less than 0.9 ppm especially in terms of the Na content issuperior in terms of the electrophotographic characteristics requiredfor an electrophotographic light receiving member.

The present invention will be further described in detail with referenceto the following examples, which are only for illustrative purposes andnot intended to restrict the scope of the invention to these examplesonly.

EXAMPLE 1

The procedures of Experiment 5 were repeated, except that thelayer-forming conditions were changed to those shown in Table 35, tothereby obtain a plurality of electrophotographic light receivingmembers each having a two-layered light receiving layer.

The resultant electrophotographic light receiving members were evaluatedin accordance with the evaluation manner described in Experiment 1. Theresults obtained were found to be satisfactory as well as theelectrophotographic light receiving members obtained in Experiment 5.

EXAMPLE 2

The procedures of Experiment 5 were repeated, except that thelayer-forming conditions were changed to those shown in Table 36, tothereby obtain a plurality of electrophotographic light receivingmembers each having a three-layered light receiving layer.

The resultant electrophotographic light receiving members were evaluatedin accordance with the evaluation manner described in Experiment 1. Theresults obtained were found to be satisfactory as well as theelectrophotographic light receiving members obtained in Experiment 5.

EXAMPLE 3

The procedures of Example 1 were repeated, except that no raw materialalloy was used upon forming the second layer, to thereby obtain aplurality of electrophotographic light receiving members each having atwo-layered light receiving layer.

The resultant electrophotographic light receiving members were evaluatedin accordance with the evaluation manner described in Experiment 1. Theresults obtained were found to be satisfactory as well as theelectrophotographic light receiving members obtained in Experiment 5.

EXAMPLE 4

The procedures of Example 1 were repeated, except that no raw materialalloy was used upon forming the first layer, to thereby obtain aplurality of electrophotographic light receiving members each having atwo-layered light receiving layer.

The resultant electrophotographic light receiving members were evaluatedin accordance with the evaluation manner described in Experiment 1. Theresults obtained were found to be satisfactory as well as theelectrophotographic light receiving members obtained in Experiment 5.

EXAMPLE 5

The procedures of Example 1 were repeated, except that no B₂ H₆ /H₂ gaswas used upon forming the second layer, to thereby obtain a plurality ofelectrophotographic light receiving members each having a two-layeredlight receiving layer.

The resultant electrophotographic light receiving members were evaluatedin accordance with the evaluation manner described in Experiment 1. Theresults obtained were found to be satisfactory as well as theelectrophotographic light receiving members obtained in Experiment 5.

EXAMPLE 6

The procedures of Experiment 10 were repeated, except that the B₂ H₆ /H₂gas was replaced by PH₃ /H₂ gas (diluted to 2000 ppm) and its flow ratewas made to be 10 sccm upon forming the first layer, to thereby obtain aplurality of electrophotographic light receiving members each having atwo-layered light receiving layer.

The resultant electrophotographic light receiving members were evaluatedin accordance with the evaluation manner described in Experiment 10. Theresults obtained were found to be satisfactory as well as theelectrophotographic light receiving members obtained in Experiment 10.

EXAMPLE 7

The procedures of Experiment 10 were repeated, except that a third layerwas formed on the second layer under the conditions shown in Table 37,to thereby obtain a plurality of electrophotographic light receivingmembers each having a three-layered light receiving layer.

The resultant electrophotographic light receiving members were evaluatedin accordance with the evaluation manner described in Experiment 10. Theresults obtained were found to be satisfactory as well as theelectrophotographic light receiving members obtained in Experiment 10.

EXAMPLE 8

The procedures of Experiment 14 were repeated, except that the GeH₄ gaswas replaced by SnH₄ gas (purity: 99.99%), to thereby obtain a pluralityof electrophotographic light receiving members each having a two-layeredlight receiving layer.

The resultant electrophotographic light receiving members were evaluatedin accordance with the evaluation manner described in Experiment 14. Theresults obtained were found to be satisfactory as well as theelectrophotographic light receiving members obtained in Experiment 14.

EXAMPLE 9

The procedures of Experiment 14 were repeated, except that the B₂ H₆ /H₂gas was replaced by PH₃ /H₂ gas (diluted to 2000 ppm) and its flow ratewas made to be 10 sccm upon forming the first layer, to thereby obtain aplurality of electrophotographic light receiving members each having atwo-layered light receiving layer.

The resultant electrophotographic light receiving members were evaluatedin accordance with the evaluation manner described in Experiment 14. Theresults obtained were found to be satisfactory as well as theelectrophotographic light receiving members obtained in Experiment 14.

EXAMPLE 10

The procedures of Experiment 14 were repeated, except that instead ofthe first layer, a two-layered first layer was formed under theconditions shown in Table 38, to thereby obtain a plurality ofelectrophotographic light receiving members.

The resultant electrophotographic light receiving members were evaluatedin accordance with the evaluation manner described in Experiment 14. Theresults obtained were found to be satisfactory as well as theelectrophotographic light receiving members obtained in Experiment 14.

EXAMPLE 11

The procedures of Experiment 14 were repeated, except that the firstlayer-forming conditions in Example 9 were employed and a third layerwas formed on the second layer under the conditions shown in Table 39,to thereby obtain a plurality of electrophotographic light receivingmembers each having a three-layered light receiving layer.

The resultant electrophotographic light receiving members were evaluatedin accordance with the evaluation manner described in Experiment 14. Theresults obtained were found to be satisfactory as well as theelectrophotographic light receiving members obtained in Experiment 14.

EXAMPLE 12

In accordance with the foregoing film-forming manner using the apparatusshown in FIG. 8 and under the conditions shown in Table 40, there wereprepared a plurality of electrophotographic light receiving members eachhaving a multi-layered light receiving layer and a test sample havingthe same light receiving layer as in the above. As the substrate foreach electrophotographic light receiving member, there was used acylindrical aluminum substrate of 80 mm in outer diameter and having anuneven surface shape provided with irregularities composed of aplurality of spherical dimples which had been formed in accordance withthe manner described in Japanese Unexamined Patent Publication No.231561/1986.

As for the resultant electrophotographic light receiving member, thecontent of each metal atoms contained in the second layer of the lightreceiving layer was examined by the SIMS. The examined results obtainedare shown in Table 41.

And as for the remaining electrophotographic light receiving members andthe test sample, evaluation was conducted in accordance with theevaluation manner described in Experiment 14. The evaluated resultsobtained are collectively shown in Table 41. As apparent from theresults shown in Table 41, it is understood that the electrophotographiclight receiving members obtained in this example are satisfactory interms of the electrophotographic characteristics as well as theelectrophotographic light receiving members obtained in Experiment 14.

                                      TABLE 1                                     __________________________________________________________________________                  raw material                                                                  alloy used                                                             gas used and                                                                         and its                                                                             substrate  inner                                                                              layer                                     name of                                                                              its flow rate                                                                        composition                                                                         temperature                                                                         RF power                                                                           pressure                                                                           thickness                                 layer  (sccm) (atomic %)                                                                          (°C.)                                                                        (mW/cm.sup.3)                                                                      (Torr)                                                                             (μm)                                   __________________________________________________________________________    electro-      Si 98.70                                                        photographic                                                                         SiH.sub.4                                                                         300                                                                              Cr 0.20                                                         light         Fe 0.20                                                                             250   25   0.5  25                                        receiving                                                                            H.sub.2                                                                           500                                                                              Mg 0.35                                                         layer         Na 0.35                                                                       Ni 0.20                                                         __________________________________________________________________________

                                      TABLE 2                                     __________________________________________________________________________                         reflection                                                                         dot        total spin                               content (atomic ppm) density                                                                            appearance                                                                          charge                                                                             density                                  Cr       Fe Mg Na Ni ratio                                                                              ratio mobility                                                                           ratio                                    __________________________________________________________________________    Example 1                                                                           0.64                                                                             0.68                                                                             0.73                                                                             0.68                                                                             0.60                                                                             1.08 1.0   1.00 1.0                                      Comparative                                                                         0.66           1.22 3.9   0.30 4.5                                      Example 1                                                                     Comparative                                                                            0.68        1.17 2.6   0.35 3.9                                      Examp1e 2                                                                     Comparative 0.71     1.20 3.5   0.23 3.3                                      Example 3                                                                     Comparative    0.68  1.18 3.1   0.26 2.9                                      Example 4                                                                     Comparative       0.61                                                                             1.20 4.2   0.22 4.7                                      Example 5                                                                     __________________________________________________________________________

                  TABLE 3                                                         ______________________________________                                                     composition of raw                                                            material alloys (atomic %)                                                    Si   Cr     Fe     Mg   Na   Ni                                  ______________________________________                                        Example 2-1    99.86  0.02   0.02 0.04 0.04 0.02                              Example 2-2    98.45  0.25   0.25 0.40 0.40 0.25                              Comparative Example 6-1                                                                      97.85  0.35   0.35 0.55 0.55 0.35                              Comparative Example 6-2                                                                      96.90  0.50   0.50 0.80 0.80 0.50                              ______________________________________                                    

                                      TABLE 4                                     __________________________________________________________________________                         reflection                                                                         dot        total spin                               content (atomic ppm) density                                                                            appearance                                                                          charge                                                                             density                                  Cr       Fe Mg Na Ni ratio                                                                              ratio mobility                                                                           ratio                                    __________________________________________________________________________    Example 2-1                                                                         0.05                                                                             0.07                                                                             0.08                                                                             0.07                                                                             0.06                                                                             1.09 1.2   0.95 1.0                                      Example 2-1                                                                         0.82                                                                             0.85                                                                             0.86                                                                             0.83                                                                             0.77                                                                             1.12 1.5   0.72 1.6                                      Comparative                                                                         1.21                                                                             1.28                                                                             1.24                                                                             1.22                                                                             1.18                                                                             1.21 2.5   0.43 2.4                                      Example 6-1                                                                   Comparative                                                                         1.58                                                                             1.81                                                                             1.79                                                                             1.64                                                                             1.52                                                                             1.25 3.4   0.26 3.5                                      Example 6-2                                                                   __________________________________________________________________________

                                      TABLE 5                                     __________________________________________________________________________                  raw material                                                                  alloy used                                                             gas used and                                                                         and its                                                                             substrate  inner                                                                              layer                                     name of                                                                              its flow rate                                                                        composition                                                                         temperature                                                                         μW power                                                                        pressure                                                                           thickness                                 layer  (sccm) (atomic %)                                                                          (°C.)                                                                        (mW/cm.sup.3)                                                                      (Torr)                                                                             (μm)                                   __________________________________________________________________________    electro-      Si 99.30                                                        photographic                                                                         SiH.sub.4                                                                         500                                                                              Cr 0.10                                                         light         Fe 0.10                                                                             300   0.5  1    25                                        receiving                                                                     layer  SiF.sub.4                                                                         20 Mg 0.20                                                                       Na 0.20                                                                       Ni 0.10                                                         __________________________________________________________________________

                                      TABLE 6                                     __________________________________________________________________________                         reflection                                                                         dot        total spin                               content (atomic ppm) density                                                                            appearance                                                                          charge                                                                             density                                  Cr       Fe Mg Na Ni ratio                                                                              ratio mobility                                                                           ratio                                    __________________________________________________________________________    Example 3                                                                           0.65                                                                             0.71                                                                             0.75                                                                             0.68                                                                             0.61                                                                             1.09 1.1   0.90                                                                              1.2                                       __________________________________________________________________________

                                      TABLE 7                                     __________________________________________________________________________                  raw material                                                                  alloy used                                                             gas used and                                                                         and its                                                                             substrate  inner                                                                              layer                                            its flow rate                                                                        composition                                                                         temperature                                                                         RF power                                                                           pressure                                                                           thickness                                 chamber                                                                              (sccm) (atomic %)                                                                          (°C.)                                                                        (W)  (Torr)                                                                             (μm)                                   __________________________________________________________________________    I.sub.1       Si 98.70                                                               SiH.sub.4                                                                         10 Cr 0.20                                                                       Fe 0.20                                                                             260   20   0.1  0.4                                              H.sub.2                                                                           50 Mg 0.35                                                                       Na 0.35                                                                       Ni 0.20                                                         __________________________________________________________________________

                                      TABLE 8                                     __________________________________________________________________________                              change of rate                                                                in external                                                                           efficiency                                                       survival                                                                           quantum retention                                   content (atomic ppm) rate efficiency                                                                            rate                                        Cr       Fe Mg Na Ni (%)  (%)     (%)                                         __________________________________________________________________________    Example 4                                                                           0.72                                                                             0.69                                                                             0.71                                                                             0.70                                                                             0.61                                                                             78   81      94                                          Comparative                                                                         0.67           60   123     86                                          Example 7                                                                     Comparative                                                                            0.69        56   97      79                                          Example 8                                                                     Comparative 0.69     62   145     93                                          Example 9                                                                     Comparative    0.72  54   133     86                                          Example 10                                                                    Comparative       0.60                                                                             58   99      89                                          Example 11                                                                    __________________________________________________________________________

                                      TABLE 9                                     __________________________________________________________________________                  raw material                                                                  alloy used                                                            gas used and                                                                          and its                                                                             substrate  inner                                                                              layer                                     name of                                                                             its flow rate                                                                         composition                                                                         temperature                                                                         RF power                                                                           pressure                                                                           thickness                                 layer (sccm)  (atomic %)                                                                          (°C.)                                                                        (mW/cm.sup.3)                                                                      (Torr)                                                                             (μm)                                   __________________________________________________________________________    electro-      Si 98.70                                                        photographic                                                                        SiH.sub.4                                                                          300                                                                              Cr 0.20                                                         light H.sub.2                                                                            500                                                                              Fe 0.20                                                                             250   25   0.5  25                                        receiving                                                                           B.sub.2 H.sub.6 /H.sub.2                                                           15 Mg 0.35                                                         layer (10 ppm Na 0.35                                                               diluted)                                                                              Ni 0.20                                                         __________________________________________________________________________

                                      TABLE 10                                    __________________________________________________________________________                         reflection                                                                         dot        total spin                               content (atomic ppm) density                                                                            appearance                                                                          charge                                                                             density                                  Cr       Fe Mg Na Ni ratio                                                                              ratio mobility                                                                           ratio                                    __________________________________________________________________________    Example 5                                                                           0.65                                                                             0.67                                                                             0.74                                                                             0.69                                                                             0.59                                                                             1.07 1.0   1.00                                                                              1.0                                       Comparative                                                                         0.66           1.24 3.9   0.25                                                                              4.6                                       Example 12                                                                    Comparative                                                                            0.68        1.17 3.0   0.35                                                                              3.8                                       Example 13                                                                    Comparative 0.72     1.20 3.3   0.25                                                                              3.4                                       Example 14                                                                    Comparative    0.68  1.18 3.5   0.31                                                                              2.8                                       Example 15                                                                    Comparative       0.61                                                                             1.19 4.1   0.26                                                                              4.3                                       Example 16                                                                    __________________________________________________________________________

                  TABLE 11                                                        ______________________________________                                                     composition of raw                                                            material alloys (atomic %)                                                    Si   Cr     Fe     Mg   Na   Ni                                  ______________________________________                                        Example 6-1    99.86  0.02   0.02 0.04 0.04 0.02                              Example 6-2    98.45  0.25   0.25 0.40 0.40 0.25                              Comparative Example 17-1                                                                     97.85  0.35   0.35 0.55 0.55 0.35                              Comparative Example 17-2                                                                     96.90  0.50   0.50 0.80 0.80 0.50                              ______________________________________                                    

                                      TABLE 12                                    __________________________________________________________________________                         reflection                                                                         dot        total spin                               content (atomic ppm) density                                                                            appearance                                                                          charge                                                                             density                                  Cr       Fe Mg Na Ni ratio                                                                              ratio mobility                                                                           ratio                                    __________________________________________________________________________    Example 6-1                                                                         0.06                                                                             0.07                                                                             0.07                                                                             0.08                                                                             0.05                                                                             1.09 1.1   0.93 1.1                                      Example 6-1                                                                         0.81                                                                             0.86                                                                             0.88                                                                             0.82                                                                             0.76                                                                             1.10 1.4   0.74 1.5                                      Comparative                                                                         1.22                                                                             1.25                                                                             1.26                                                                             1.21                                                                             1.19                                                                             1.23 2.5   0.39 2.5                                      Example 17-1                                                                  Comparative                                                                         1.60                                                                             1.79                                                                             1.85                                                                             1.65                                                                             1.54                                                                             1.26 3.5   0.26 3.4                                      Example 17-2                                                                  __________________________________________________________________________

                                      TABLE 13                                    __________________________________________________________________________                  raw material                                                                  alloy used                                                            gas used and                                                                          and its                                                                             substrate  inner                                                                              layer                                     name of                                                                             its flow rate                                                                         composition                                                                         temperature                                                                         μW power                                                                        pressure                                                                           thickness                                 layer (sccm)  (atomic %)                                                                          (°C.)                                                                        (mW/cm.sup.3)                                                                      (Torr)                                                                             (μm)                                   __________________________________________________________________________    electro-      Si 99.70                                                        photographic                                                                        SiH.sub.4                                                                          500                                                                              Cr 0.10                                                         light SiF.sub.4                                                                          20 Fe 0.10                                                                             300   0.5  1    30                                        receiving                                                                           B.sub.2 H.sub.6 /H.sub.2                                                           10 Mg 0.20                                                         layer (100 ppm                                                                              Na 0.20                                                               diluted)                                                                              Ni 0.10                                                         __________________________________________________________________________

                                      TABLE 14                                    __________________________________________________________________________                         reflection                                                                         dot        total spin                               content (atomic ppm) density                                                                            appearance                                                                          charge                                                                             density                                  Cr       Fe Mg Na Ni ratio                                                                              ratio mobility                                                                           ratio                                    __________________________________________________________________________    Example 7                                                                           0.66                                                                             0.72                                                                             0.76                                                                             0.67                                                                             0.63                                                                             1.07 1.1   0.94                                                                              1.1                                       __________________________________________________________________________

                                      TABLE 15                                    __________________________________________________________________________                  raw material                                                                  alloy used                                                            gas used and                                                                          and its                                                                             substrate  inner                                                                              layer                                           its flow rate                                                                         composition                                                                         temperature                                                                         RF power                                                                           pressure                                                                           thickness                                 chamber                                                                             (sccm)  (atomic %)                                                                          (°C.)                                                                        (W)  (Torr)                                                                             (μm)                                   __________________________________________________________________________    I.sub.2       Si 98.70                                                              SiH.sub.4                                                                          10 Cr 0.20                                                               H.sub.2                                                                            50 Fe 0.20                                                                             260   20   0.1  0.4                                             PH.sub.3 /H.sub.2                                                                  5  Mg 0.35                                                               (220 ppm)                                                                             Na 0.35                                                                       Ni 0.20                                                         __________________________________________________________________________

                                      TABLE 16                                    __________________________________________________________________________                              change of rate                                                                in external                                                                           efficiency                                                       survival                                                                           quantum retention                                   content (atomic ppm) rate efficiency                                                                            rate                                        Cr       Fe Mg Na Ni (%)  (%)     (%)                                         __________________________________________________________________________    Example 8                                                                           0.71                                                                             0.75                                                                             0.77                                                                             0.81                                                                             0.60                                                                             68   99      90                                          Comparative                                                                         0.69           58   151     85                                          Example 18                                                                    Comparative                                                                            0.69        54   109     79                                          Example 19                                                                    Comparative 0.71     62   154     91                                          Example 20                                                                    Comparative    0.69  52   163     84                                          Example 21                                                                    Comparative       0.55                                                                             58   102     85                                          Example 22                                                                    __________________________________________________________________________

                                      TABLE 17                                    __________________________________________________________________________                  raw material                                                                  alloy used                                                            gas used and                                                                          and its                                                                             substrate  inner                                                                              layer                                           its flow rate                                                                         composition                                                                         temperature                                                                         RF power                                                                           pressure                                                                           thickness                                 chamber                                                                             (sccm)  (atomic %)                                                                          (°C.)                                                                        (W)  (Torr)                                                                             (μm)                                   __________________________________________________________________________    N     Ar   38                                                                       SiH.sub.4                                                                          0.2      270   20   0.1  0.01                                            H.sub.2                                                                            0.4                                                                      PH.sub.3                                                                           0.4                                                                I.sub.1                                                                             SiH.sub.4                                                                          10 Si 98.70                                                              H.sub.2                                                                            40 Cr 0.20                                                               BF.sub.3 /H.sub.2                                                                  3  Fe 0.20                                                                             260   20   0.1  0.4                                             (150 ppm)                                                                             Mg 0.35                                                                       Na 0.35                                                                       Ni 0.20                                                         P     SiH.sub.4                                                                          0.1                                                                      H.sub.2                                                                            70       250   120  0.1  0.01                                            BF.sub.3                                                                           0.05                                                               __________________________________________________________________________

                                      TABLE 18                                    __________________________________________________________________________                              change of rate                                                                in external                                                                           efficiency                                                       survival                                                                           quantum retention                                   content (atomic ppm) rate efficiency                                                                            rate                                        Cr       Fe Mg Na Ni (%)  (%)     (%)                                         __________________________________________________________________________    Example 9                                                                           0.85                                                                             0.74                                                                             0.67                                                                             0.76                                                                             0.64                                                                             88   84      95                                          Comparative                                                                         0.74           74   121     89                                          Example 23                                                                    Comparative                                                                            0.75        66   101     79                                          Example 24                                                                    Comparative 0.54     72   113     93                                          Example 25                                                                    Comparative    0.78  74   145     91                                          Example 26                                                                    Comparative       0.61                                                                             76   97      89                                          Example 27                                                                    __________________________________________________________________________

                                      TABLE 19                                    __________________________________________________________________________                  raw material                                                                  alloy used                                                            gas used and                                                                          and its                                                                             substrate  inner                                                                              layer                                     name of                                                                             its flow rate                                                                         composition                                                                         temperature                                                                         RF power                                                                           pressure                                                                           thickness                                 layer (sccm)  (atomic %)                                                                          (°C.)                                                                        (mW/cm.sup.3)                                                                      (Torr)                                                                             (μm)                                   __________________________________________________________________________    first layer                                                                         SiH.sub.4                                                                          500                                                                      H.sub.2                                                                            500      250   10   0.4  3                                               B.sub.2 H.sub.6 /H.sub.2                                                           20                                                                       (3000 ppm                                                                     diluted)                                                                second layer  Si 98.70                                                              SiH.sub.4                                                                          300                                                                              Cr 0.20                                                                       Fe 0.20                                                                             250   25   0.5  25                                              H.sub.2                                                                            500                                                                              Mg 0.35                                                                       Na 0.35                                                                       Ni 0.20                                                         __________________________________________________________________________

                                      TABLE 20                                    __________________________________________________________________________                         reflection                                                                         dot        total spin                               content (atomic ppm) density                                                                            appearance                                                                          charge                                                                             density                                  Cr       Fe Mg Na Ni ratio                                                                              ratio mobility                                                                           ratio                                    __________________________________________________________________________    Example 10                                                                          0.64                                                                             0.68                                                                             0.73                                                                             0.68                                                                             0.60                                                                             1.08 1.0   1.00 1.0                                      Comparative                                                                         0.66           1.23 3.8   0.31 4.5                                      Example 28                                                                    Comparative                                                                            0.68        1.17 2.7   0.36 3.9                                      Example 29                                                                    Comparative 0.71     1.21 3.4   0.22 3.3                                      Example 30                                                                    Comparative    0.68  1.17 3.3   0.27 2.9                                      Example 31                                                                    Comparative       0.61                                                                             1.20 4.4   0.21 4.7                                      Example 32                                                                    __________________________________________________________________________

                  TABLE 21                                                        ______________________________________                                                     composition of raw                                                            material alloys (atomic %)                                                    Si   Cr     Fe     Mg   Na   Ni                                  ______________________________________                                        Example 11-1   99.86  0.02   0.02 0.04 0.04 0.02                              Example 11-2   98.45  0.25   0.25 0.40 0.40 0.25                              Comparative Example 33-1                                                                     97.85  0.35   0.35 0.55 0.55 0.35                              Comparative Example 33-2                                                                     96.90  0.50   0.50 0.80 0.80 0.50                              ______________________________________                                    

                                      TABLE 22                                    __________________________________________________________________________                         reflection                                                                         dot        total spin                               content (atomic ppm) density                                                                            appearance                                                                          charge                                                                             density                                  Cr       Fe Mg Na Ni ratio                                                                              ratio mobility                                                                           ratio                                    __________________________________________________________________________    Example 11-1                                                                        0.05                                                                             0.07                                                                             0.08                                                                             0.07                                                                             0.06                                                                             1.10 1.1   0.96 1.0                                      Example 11-2                                                                        0.82                                                                             0.85                                                                             0.86                                                                             0.83                                                                             0.77                                                                             1.12 1.5   0.73 1.6                                      Comparative                                                                         1.21                                                                             1.28                                                                             1.24                                                                             1.22                                                                             1.18                                                                             1.22 2.4   0.42 2.4                                      Example 33-1                                                                  Comparative                                                                         1.58                                                                             1.81                                                                             1.79                                                                             1.64                                                                             1.52                                                                             1.27 3.5   0.27 3.5                                      Example 33-2                                                                  __________________________________________________________________________

                                      TABLE 23                                    __________________________________________________________________________                  raw material                                                                  alloy used                                                            gas used and                                                                          and its                                                                             substrate  inner                                                                              layer                                     name of                                                                             its flow rate                                                                         composition                                                                         temperature                                                                         μW power                                                                        pressure                                                                           thickness                                 layer (sccm)  (atomic %)                                                                          (°C.)                                                                        (mW/cm.sup.3)                                                                      (Torr)                                                                             (μm)                                   __________________________________________________________________________    first layer                                                                         SiH.sub.4                                                                          500                                                                      SiF.sub.4                                                                          100      300   0.5  1.2  3                                               B.sub.2 H.sub.6 /H.sub.2                                                           50                                                                       (1%                                                                           diluted)                                                                second layer  Si 99.70                                                              SiH.sub.4                                                                          500                                                                              Gr 0.10                                                                       Fe 0.10                                                                             300   0.5  1    25                                              SiF.sub.4                                                                          20 Mg 0.20                                                                       Na 0.20                                                                       Ni 0.10                                                         __________________________________________________________________________

                                      TABLE 24                                    __________________________________________________________________________                         reflection                                                                         dot        total spin                               content (atomic ppm) density                                                                            appearance                                                                          charge                                                                             density                                  Cr       Fe Mg Na Ni ratio                                                                              ratio mobility                                                                           ratio                                    __________________________________________________________________________    Example 7                                                                           0.66                                                                             0.71                                                                             0.75                                                                             0.68                                                                             0.61                                                                             1.08 1.2   0.95 1.2                                      __________________________________________________________________________

                                      TABLE 25                                    __________________________________________________________________________                  raw material                                                                  alloy used                                                            gas used and                                                                          and its                                                                             substrate  inner                                                                              layer                                           its flow rate                                                                         composition                                                                         temperature                                                                         RF power                                                                           pressure                                                                           thickness                                 chamber                                                                             (sccm)  (atomic %)                                                                          (°C.)                                                                        (W)  (Torr)                                                                             (μm)                                   __________________________________________________________________________    N     Ar   38                                                                       SiH.sub.4                                                                          0.2      270   20   0.1  0.01                                            H.sub.2                                                                            0.4                                                                      PH.sub.3                                                                           0.4                                                                I.sub.1       Si 98.70                                                              SiH.sub.4                                                                          10 Cr 0.20                                                                       Fe 0.20                                                                             260   20   0.1  0.4                                             H.sub.2                                                                            40 Mg 0.35                                                                       Na 0.35                                                                       Ni 0.20                                                         P     SiH.sub.4                                                                          0.1                                                                      H.sub.2                                                                            70       250   120  0.1  0.01                                            BF.sub.3                                                                           0.05                                                               __________________________________________________________________________

                                      TABLE 26                                    __________________________________________________________________________                              change of rate                                                                in external                                                                           efficiency                                                       survival                                                                           quantum retention                                   content (atomic ppm) rate efficiency                                                                            rate                                        Cr       Fe Mg Na Ni (%)  (%)     (%)                                         __________________________________________________________________________    Example 13                                                                          0.69                                                                             0.68                                                                             0.78                                                                             0.73                                                                             0.85                                                                             86   71      96                                          Comparative                                                                         0.74           72   113     88                                          Example 34                                                                    Comparative                                                                            0.81        66   90      81                                          Example 35                                                                    Comparative 0.71     68   124     94                                          Example 36                                                                    Comparative    0.69  68   112     91                                          Example 37                                                                    Comparative       0.79                                                                             62   91      92                                          Example 38                                                                    __________________________________________________________________________

                                      TABLE 27                                    __________________________________________________________________________                  raw material                                                                  alloy used                                                            gas used and                                                                          and its                                                                             substrate  inner                                                                              layer                                     name of                                                                             its flow rate                                                                         composition                                                                         temperature                                                                         RF power                                                                           pressure                                                                           thickness                                 layer (sccm)  (atomic %)                                                                          (°C.)                                                                        (mW/cm.sup.3)                                                                      (Torr)                                                                             (μm)                                   __________________________________________________________________________    first layer                                                                         SiH.sub.4                                                                          100                                                                      H.sub.2                                                                            500      250   10   0.4  3                                               B.sub.2 H.sub.6 /H.sub.2                                                           30                                                                       (3000 ppm                                                                     diluted)                                                                      GeH.sub.4                                                                          20                                                                 second layer  Si 98.70                                                              SiH.sub.4                                                                          300                                                                              Cr 0.20                                                                       Fe 0.20                                                                             250   25   0.5  25                                              H.sub.2                                                                            500                                                                              Mg 0.35                                                                       Na 0.35                                                                       Ni 0.20                                                         __________________________________________________________________________

                                      TABLE 28                                    __________________________________________________________________________                         reflection                                                                         dot        total spin                               content (atomic ppm) density                                                                            appearance                                                                          charge                                                                             density                                  Cr       Fe Mg Na Ni ratio                                                                              ratio mobility                                                                           ratio                                    __________________________________________________________________________    Example 14                                                                          0.64                                                                             0.68                                                                             0.73                                                                             0.68                                                                             0.60                                                                             1.07 1.0   1.00 1.0                                      Comparative                                                                         0.66           1.22 3.9   0.32 4.8                                      Example 39                                                                    Comparative                                                                            0.68        1.18 2.8   0.35 3.6                                      Example 40                                                                    Comparative 0.71     1.23 3.9   0.24 3.6                                      Example 41                                                                    Comparative    0.68  1.18 3.4   0.26 2.8                                      Example 42                                                                    Comparative       0.61                                                                             1.19 4.4   0.25 4.4                                      Example 43                                                                    __________________________________________________________________________

                  TABLE 29                                                        ______________________________________                                                     composition of raw                                                            material alloys (atomic %)                                                    Si   Cr     Fe     Mg   Na   Ni                                  ______________________________________                                        Example 15-1   99.86  0.02   0.02 0.04 0.04 0.02                              Example 15-2   98.45  0.25   0.25 0.40 0.40 0.25                              Comparative Example 44-1                                                                     97.85  0.35   0.35 0.55 0.55 0.35                              Comparative Example 44-2                                                                     96.90  0.50   0.50 0.80 0.80 0.50                              ______________________________________                                    

                                      TABLE 30                                    __________________________________________________________________________                         reflection                                                                         dot        total spin                               content (atomic ppm) density                                                                            appearance                                                                          charge                                                                             density                                  Cr       Fe Mg Na Ni ratio                                                                              ratio mobility                                                                           ratio                                    __________________________________________________________________________    Example 15-1                                                                        0.05                                                                             0.07                                                                             0.08                                                                             0.07                                                                             0.06                                                                             1.09 1.1   0.94 1.0                                      Example 15-2                                                                        0.82                                                                             0.85                                                                             0.86                                                                             0.83                                                                             0.77                                                                             1.11 1.5   0.75 1.4                                      Comparative                                                                         1.21                                                                             1.28                                                                             1.24                                                                             1.22                                                                             1.18                                                                             1.23 2.5   0.39 2.6                                      Example 44-1                                                                  Comparative                                                                         1.58                                                                             1.81                                                                             1.79                                                                             1.64                                                                             1.52                                                                             1.27 3.4   0.28 3.7                                      Example 44-2                                                                  __________________________________________________________________________

                                      TABLE 31                                    __________________________________________________________________________                  raw material                                                                  alloy used                                                            gas used and                                                                          and its                                                                             substrate  inner                                                                              layer                                           its flow rate                                                                         composition                                                                         temperature                                                                         RF power                                                                           pressure                                                                           thickness                                 chamber                                                                             (sccm)  (atomic %)                                                                          (°C.)                                                                        (W)  (Torr)                                                                             (μm)                                   __________________________________________________________________________    N     Ar   38                                                                       SiH.sub.4                                                                          0.2      270   20   0.1  0.01                                            H.sub.2                                                                            0.4                                                                      PH.sub.3                                                                           0.4                                                                I.sub.1                                                                             SiH.sub.4                                                                          10                                                                       GeH.sub.4                                                                          0.5      265   20   0.1  0.1                                             H.sub.2                                                                            40                                                                 I.sub.2       Si 98.70                                                              SiH.sub.4                                                                          10 Cr 0.20                                                                       Fe 0.20                                                                             260   20   0.1  0.4                                             H.sub.2                                                                            40 Mg 0.35                                                                       Na 0.35                                                                       Ni 0.20                                                         P     SiH.sub.4                                                                          0.1                                                                      H.sub.2                                                                            70       250   120  0.1  0.01                                            BF.sub.3                                                                           0.05                                                               __________________________________________________________________________

                                      TABLE 32                                    __________________________________________________________________________                              change of rate                                                                in external                                                                           efficiency                                                       survival                                                                           quantum retention                                   content (atomic ppm) rate efficiency                                                                            rate                                        Cr       Fe Mg Na Ni (%)  (%)     (%)                                         __________________________________________________________________________    Example 16                                                                          0.73                                                                             0.71                                                                             0.84                                                                             0.72                                                                             0.81                                                                             88   69      96                                          Comparative                                                                         0.69           74   104     89                                          Example 45                                                                    Comparative                                                                            0.74        66   114     82                                          Example 46                                                                    Comparative 0.73     86   99      94                                          Example 47                                                                    Comparative    0.68  72   102     92                                          Example 48                                                                    Comparative       0.78                                                                             82   95      95                                          Example 49                                                                    __________________________________________________________________________

                                      TABLE 33                                    __________________________________________________________________________                         reflection                                                                         dot        total spin                               Sample                                                                              content (atomic ppm)                                                                         density                                                                            appearance                                                                          charge                                                                             density                                  No.   Cr Fe Mg Na Ni ratio                                                                              ratio mobility                                                                           ratio                                    __________________________________________________________________________    1     0.1                                                                              0.68                                                                             0.73                                                                             0.68                                                                             0.60                                                                             1.03 0.99  0.98 0.99                                     2     0.3                                                                              0.68                                                                             0.73                                                                             0.68                                                                             0.60                                                                             1.06 0.98  0.99 0.98                                     3     0.64                                                                             0.68                                                                             0.73                                                                             0.68                                                                             0.60                                                                             1.08 1.0   1.00 1.0                                      4     0.90                                                                             0.68                                                                             0.73                                                                             0.68                                                                             0.60                                                                             1.01 1.01  0.99 1.01                                     5     1.0                                                                              0.68                                                                             0.73                                                                             0.68                                                                             0.60                                                                             1.15 2.3   0.39 2.5                                      __________________________________________________________________________

                                      TABLE 34                                    __________________________________________________________________________                         reflection                                                                         dot        total spin                               Sample                                                                              content (atomic ppm)                                                                         density                                                                            appearance                                                                          charge                                                                             density                                  No.   Cr Fe Mg Na Ni ratio                                                                              ratio mobility                                                                           ratio                                    __________________________________________________________________________    1     0.64                                                                             0.68                                                                             0.73                                                                             0.1                                                                              0.60                                                                             1.02 0.97  0.97 0.96                                     2     0.64                                                                             0.68                                                                             0.73                                                                             0.3                                                                              0.60                                                                             1.05 0.99  1.01 0.98                                     3     0.64                                                                             0.68                                                                             0.73                                                                             0.68                                                                             0.60                                                                             1.08 1.0   1.00 1.0                                      4     0.64                                                                             0.68                                                                             0.73                                                                             0.9                                                                              0.60                                                                             1.08 1.02  0.98 1.02                                     5     0.64                                                                             0.68                                                                             0.73                                                                             1.0                                                                              0.60                                                                             1.20 2.7   0.40 3.1                                      __________________________________________________________________________

                                      TABLE 35                                    __________________________________________________________________________                   raw material                                                                  alloy used                                                           gas used and                                                                           and its substrate  inner                                                                              layer                                  name of                                                                             its flow rate                                                                          composition                                                                           temperature                                                                         RF power                                                                           pressure                                                                           thickness                              layer (sccm)   (atomic %)                                                                            (°C.)                                                                        (mW/cm.sup.3)                                                                      (Torr)                                                                             (μm)                                __________________________________________________________________________    first layer     Si 98.70                                                            SiH.sub.4                                                                           150 Cr 0.20                                                             H.sub.2                                                                             500 Fe 0.20                                                                              250   10   0.4  3                                            B.sub.2 H.sub.6 /H.sub.2                                                            50  Mg 0.35                                                             (3000 ppm Na 0.35                                                             diluted)                                                                                Ni 0.20                                                       second layer    Si 98.70                                                            SiH.sub.4                                                                           300 Cr 0.20                                                             H.sub.2                                                                             500 Fe 0.20                                                                              250   25   0.5  25                                           B.sub.2 H.sub.6 /H.sub.2                                                            10  Mg 0.35                                                             (10 ppm   Na 0.35                                                             diluted)                                                                                Ni 0.20                                                       __________________________________________________________________________

                                      TABLE 36                                    __________________________________________________________________________                   raw material                                                                  alloy used                                                           gas used and                                                                           and its substrate  inner                                                                              layer                                  name of                                                                             its flow rate                                                                          composition                                                                           temperature                                                                         RF power                                                                           pressure                                                                           thickness                              layer (sccm)   (atomic %)                                                                            (°C.)                                                                        (mW/cm.sup.3)                                                                      (Torr)                                                                             (μm)                                __________________________________________________________________________    first layer     Si 98.70                                                            SiH.sub.4                                                                           1000                                                                              Cr 0.20                                                             H.sub.2                                                                             500 Fe 0.20                                                                              250   10   0.4  3                                            PH.sub.3 /H.sub.2                                                                   25  Mg 0.35                                                             (2000 ppm Na 0.35                                                             diluted)                                                                                Ni 0.20                                                       second layer    Si 98.70                                                            SiH.sub.4                                                                           300 Cr 0.20                                                             H.sub.2                                                                             500 Fe 0.20                                                                              250   25   0.5  25                                           B.sub.2 H.sub.6 /H.sub.2                                                            5   Mg 0.35                                                             (10 ppm   Na 0.35                                                             diluted)                                                                                Ni 0.20                                                       third layer     Si 98.70                                                            SiH.sub.4                                                                           300 Cr 0.20                                                             H.sub.2                                                                             500 Fe 0.20                                                                              250   10   0.4  0.2                                          B.sub.2 H.sub.6 /H.sub.2                                                            10  Mg 0.35                                                             (3000 ppm Na 0.35                                                             diluted)                                                                                Ni 0.20                                                             SiH.sub.4                                                                           100                                                                     H.sub.2                                                                             500 --     250   10   0.4  0.2                                          PH.sub.3 /H.sub.2                                                                   3                                                                       (2000 ppm                                                                     diluted)                                                                __________________________________________________________________________

                                      TABLE 37                                    __________________________________________________________________________                   raw material                                                                  alloy used                                                           gas used and                                                                           and its substrate  inner                                                                              layer                                  name of                                                                             its flow rate                                                                          composition                                                                           temperature                                                                         RF power                                                                           pressure                                                                           thickness                              layer (sccm)   (atomic %)                                                                            (°C.)                                                                        (mW/cm.sup.3)                                                                      (Torr)                                                                             (μm)                                __________________________________________________________________________    third layer                                                                         SiH.sub.4                                                                           100                                                                     H.sub.2                                                                             500 -- 250 10    0.4  0.2                                               PH.sub.3 H.sub.2                                                                    3                                                                       (2000 ppm                                                                     diluted                                                                 __________________________________________________________________________

                                      TABLE 38                                    __________________________________________________________________________                   raw material                                                                  alloy used                                                           gas used and                                                                           and its substrate  inner                                                                              layer                                  name of                                                                             its flow rate                                                                          composition                                                                           temperature                                                                         RF power                                                                           pressure                                                                           thickness                              layer (sccm)   (atomic %)                                                                            (°C.)                                                                        (mW/cm.sup.3)                                                                      (Torr)                                                                             (μm)                                __________________________________________________________________________    first layer                                                                         SiH.sub.4                                                                           100                                                                     H.sub.2                                                                             500                                                                     B.sub.2 H.sub.6 /H.sub.2                                                            40  --     250   10   0.4  1                                            (3000 ppm                                                                     diluted)                                                                      GeH.sub.4                                                                           50                                                                additional                                                                          SiH.sub.4                                                                           100                                                               first layer                                                                         H.sub.2                                                                             500                                                                     B.sub.2 H.sub.6 /H.sub.2                                                            20  --     250   10   0.4  3                                            (3000 ppm                                                                     diluted)                                                                __________________________________________________________________________

                                      TABLE 39                                    __________________________________________________________________________                   raw material                                                                  alloy used                                                           gas used and                                                                           and its substrate  inner                                                                              layer                                  name of                                                                             its flow rate                                                                          composition                                                                           temperature                                                                         RF power                                                                           pressure                                                                           thickness                              layer (sccm)   (atomic %)                                                                            (°C.)                                                                        (mW/cm.sup.3)                                                                      (Torr)                                                                             (μm)                                __________________________________________________________________________    third layer                                                                         SiH.sub.4                                                                           100                                                                     H.sub.2                                                                             500 --     250   10   0.4  0.2                                          PH.sub.3 /H.sub.2                                                                   3                                                                       (2000 ppm                                                                     diluted)                                                                __________________________________________________________________________

                                      TABLE 40                                    __________________________________________________________________________                     raw material                                                                  alloy used                                                          gas used and                                                                            and its                                                                              substrate   inner                                                                              layer                                name of                                                                              its flow rate                                                                           composition                                                                          temperature                                                                         μW power                                                                         pressure                                                                           thickness                            layer  (sccm)    (atomic %)                                                                           (°C.)                                                                        (mW/cm.sup.3)                                                                       (Torr)                                                                             (μm)                              __________________________________________________________________________    first layer                                                                          SiH.sub.4                                                                            500                                                                              --     300   0.5   1.2  1                                           SiF.sub.4                                                                            100                                                                    B.sub.2 H.sub.6 /H.sub.2                                                             100                                                                    (1% diluted)                                                                  GeH.sub.4                                                                            200                                                             addtional                                                                            SiH.sub.4                                                                            500                                                                              --     300   0.5   1.2  3                                    first layer                                                                          SiF.sub.4                                                                            100                                                                    B.sub.2 H.sub.6 /H.sub.2                                                              50                                                                    (1% diluted)                                                           second layer                                                                         SiH.sub.4                                                                            500                                                                              Si 99.70                                                                             300   0.5   1    25                                                    Cr 0.10                                                                       Fe 0.10                                                             SiF.sub.4                                                                             20                                                                              Mg 0.20                                                                       Na 0.20                                                                       Ni 0.10                                                      __________________________________________________________________________

                                      TABLE 41                                    __________________________________________________________________________                         reflection                                                                         dot        total spin                               content (atomic ppm) density                                                                            appearance                                                                          charge                                                                             density                                  Cr       Fe Mg Na Ni ratio                                                                              ratio mobility                                                                           ratio                                    __________________________________________________________________________    Example 12                                                                          0.65                                                                             0.71                                                                             0.75                                                                             0.68                                                                             0.61                                                                             1.09 1.1   0.93 1.1                                      __________________________________________________________________________

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 and 9 are schematic views respectively illustrating an exampleof the layer configuration of an electrophotographic light receivingmember according to the present invention.

FIGS. 2 and 6 are schematic diagrams respectively illustrating theconstitution of a fabrication apparatus by the RF glow dischargedecomposition process which is suitable for the formation of a lightreceiving layer of an electrophotographic light receiving memberaccording to the present invention.

FIGS. 3 and 7 are schematic diagrams respectively illustrating theconstitution of a fabrication apparatus by the microwave glow dischargedecomposition process which is suitable for the formation of a lightreceiving layer of an electrophotographic light receiving memberaccording to the present invention.

FIGS. 4 and 8 are schematic diagrams respectively illustrating theconstitution of a fabrication apparatus by the microwave glow dischargedecomposition process which is suitable for the formation of a lightreceiving layer of an electrophotographic light receiving memberaccording to the present invention.

FIG. 5 is a schematic diagram illustrating the constitution of afabrication apparatus which is suitable for the production of a lightreceiving member usable as a solar cell according to the presentinvention.

We claim:
 1. A light receiving member comprising a substrate and a lightreceiving layer disposed on said substrate, said light receiving layerbeing composed of (A) a non-single crystal material containing siliconatoms as a matrix (B), at least one kind of atoms selected from thegroup consisting of hydrogen atoms and halogen atoms, and (C) chromiumatoms, iron atoms, nickel atoms, sodium atoms and magnesium atoms,wherein said light receiving layer contains each of said chromium atoms,iron atoms, nickel atoms, sodium atoms and magnesium atoms in an amountof 0.9 atomic ppm or less.
 2. A light receiving member according toclaim 1, wherein the light receiving layer further contains aconductivity controlling material.
 3. A light receiving member accordingto claim 2, wherein the conductivity controlling material is containedin the light receiving layer at an uneven concentration distribution. 4.A light receiving member according to claim 2, wherein the conductivitycontrolling material is contained in the light receiving layer at auniform concentration distribution.
 5. A light receiving memberaccording to claim 2, wherein the conductivity controlling material isan element selected from the group consisting of B, Al, Ga, In, Tl, P,As, Sb and Bi.
 6. A light receiving member according to claim 1, whereinthe light receiving layer has a multi-layered structure.
 7. A lightreceiving member according to claim 6, wherein at least one constituentlayer of the multi-layered structure further contains a conductivitycontrolling material.
 8. A light receiving member according to claim 7,wherein the conductivity controlling material is an element selectedfrom the group consisting of B, Al, Ga, In, Tl, P, As, Sb and Bi.
 9. Alight receiving member according to claim 6, wherein all the constituentlayers of the multi-layered structure are composed of amorphousmaterials.
 10. A light receiving member according to claim 1 whichfurther comprises a light receiving layer (a) composed of a non-singlecrystal material containing silicon atoms as a matrix, at least one kindof atoms selected from the group consisting of hydrogen atoms andhalogen atoms, and a conductivity controlling material, wherein saidlight receiving layer (a) is interposed between the substrate and thelight receiving layer.
 11. A light receiving member according to claim10, wherein the conductivity controlling material in said lightreceiving layer (a) is an element selected from the group consisting ofB, Al, Ga, In, Tl, P, As, Sb and Bi.
 12. A light receiving memberaccording to claim 10, wherein the non-single crystal material by whichthe light receiving layer (a) is constituted is an amorphous material.13. A light receiving member according to claim 1 which furthercomprises a light receiving layer (b) composed of a non-single crystalmaterial containing silicon atoms as a matrix, at least one kind ofatoms selected from the group consisting of hydrogen atoms and halogenatoms, and at least one kind of atoms selected from the group consistingof tin atoms and germanium atoms, wherein said light receiving layer (b)is interposed between the substrate and the light receiving layer.
 14. Alight receiving member according to claim 13, wherein the non-singlecrystal material by which the light receiving layer (b) is constitutedis an amorphous material.
 15. A light receiving member according toclaim 13, wherein the non-single crystal material by which the lightreceiving layer (b) is constituted further contains a conductivitycontrolling material.
 16. A light receiving member according to claim15, wherein the conductivity controlling material in said lightreceiving layer (b) is an element selected from the group consisting ofB, Al, Ga, In, Tl, P, As, Sb and Bi.
 17. A light receiving memberaccording to claim 1 which further comprises a light receiving layer (c)composed of a non-single crystal material containing silicon atoms as amatrix and at least one kind of atoms selected from the group consistingof oxygen atoms, nitrogen atoms and carbon atoms, wherein said lightreceiving layer (c) is disposed on the light receiving layer.
 18. Alight receiving member according to claim 17, wherein the non-singlecrystal material by which the light receiving layer (c) is constitutedfurther contains at least one kind of atoms selected from the groupconsisting of hydrogen atoms and halogen atoms.
 19. A light receivingmember according to claim 17, wherein the light receiving layer (c) is asurface layer.
 20. A light receiving member according to claim 17,wherein the non-single crystal material by which the light receivinglayer (c) is constituted is an amorphous material.
 21. A light receivingmember according to claim 1, wherein the non-single crystal material bywhich the light receiving layer is constituted is an amorphous material.22. An electrophotographic device comprising an electroconductivesubstance and a light receiving member according to claim 1.